Enhance Your Radio Business Now with Our Solutions!


Compact FM broadcast transmitters of rack-mounted & solid-state types for radio station, available from low power (<50 watts), medium power (50 - 1000 watts) to high power (>1000 watts).
More Info+

Solid-state and rack mounted TV transmitters from 5 watts to 10KW of digital & analog types, all-in-one module design with redundancy design for professional TV broadcasting.
More Info+

Complete FM radio station packages, 100% low-cost & high quality radio turnkey solutions, available from FM transmitter packages, complete turnkey FM radio station, radio antenna system to radio stuido equipment packages.
More Info+

High power AM broadcast transmitter, eco-friendly design with modular AUI remote control, tested >72% working efficiency, all integrated into gilt cabinet, available from 1KW to up to 200KW.
More Info+

High gain FM & TV Broadcast Antennas for radio station, available from dipole antenna, ground plane antenna,circularly polarized antenna, STL antenna, yagi antenna, panel antenna and slot antenna, etc.
More Info+

Complete studio transmitter link equipment for long range point-to-point (PTP) audio transmission, available from STL over IP, microwave STL system, STL transmitter and receiver, STL antennas.
More Info+

Contact now for more details, available from placing real-time orders , radio station setting guide, online technical support, after-sales services, business cooperation, SEO link & content exchange.
More Info+

Learn more details about FMUSER from our products, solutions to who we are, conduct a deep business talk to our RF & sales expert team and tell us your needs.
More Info+OUR COMPANY
Worldwide manufacturer and supplier of FM, AM and TV transmission equipment.
As an experienced manufacturer for FM / AM / TV broadcast equipment, FMUSER has now become one of the most price-competitive broadcast equipment supplier around the world, with more than 10,000 of affordable radio turnkey solutions successfully deployed since 2002.



We cover your need with worldwide supply, premium quality and best prices!
- IPTV Systems
- On-Air Studio
- Full Radio Station
- FM Transmitter Packages
- FM Antenna System
- Podcast Equipment
- FM Transmitters for Drive-In
- Low Power FM Transmitters
- Low Power FM Antennas
- High Power FM Transmitters
- Multi-bay FM Antennas
- STL over IP
- STL Link Transmitters and Receivers
- RF Tools
- FM Transmitter Amplifiers
- High Power RF Transistors
- RF Dummy Loads
- Coax Connectors
- RF Coaxial Cable
- Rigid Line & Components
- VHF Cavity Filters
- UHF Cavity Filters
- FM Cavity Filter
- L Band Cavity Filter
- VHF Couplers
- UHF Couplers
- L Band Coupler
- FM Combiners
- VHF Combiners
- UHF Combiners
- L Band Combiners
- AM Transmitters
- AM Medium Wave Antennas
- AM Shortwave Antenna
- AM Dummy Loads
- TV Transmitters
- TV Station Antennas
- UHF Slot Antennas
- UHF Panel Antennas
- VHF Panel Antennas
- VHF Slot Antennas
Latest News From FMUSER
You can get the latest industry information from here.

Standing Out in the Crowd: The Advantages of Customizing Hotel IPTV System for Boutique Hotels
Discover how customizing IPTV systems can set boutique hotels apart by delivering tailored content and services that showcase their unique brand identity and ultimately enhance guest satisfaction.

Maximizing Online Reputation - The Link Between Hotel IPTV System and Positive Guest Reviews
Discover how hotels can improve their online reputation and attract more guests by using an IPTV system to provide an exceptional guest experience, resulting in positive reviews and higher ratings. Read our article to know more!

Leveraging Hotel IPTV Systems for Successful Hybrid Events & Conferences
Learn how hotels can use IPTV systems for live streaming, virtual conferences, and hybrid events. Explore the benefits of IPTV, revenue generation opportunities, and cost-effectiveness.

How Hotel IPTV Systems Can Attract Gen Z and Millennial Guests
With the rise of Gen Z and Millennial travelers, hotels are turning to hotel IPTV systems as an effective solution to attract younger guests. Discover how FMUSER’s hotel IPTV solutions can enhance the guest experience with social media integration, mobile app access, and advanced guest management tools.

Enhancing Hotel Safety and Security with IPTV Systems
Learn how hotels can use IPTV systems for enhanced surveillance, access control, and emergency management to create a safer and more secure environment for guests and employees. Explore the key features and benefits of IPTV systems, ways it can be customized to suit specific hotel needs, and advantages of investing in a quality IPTV system like the ones offered by FMUSER.

Contactless Check-In/Check-Out: Enhancing Guest Experience with Hotel IPTV System
Learn how hotels can use hotel IPTV system for contactless check-in/check-out to provide guests with a more efficient, enjoyable, and secure stay. With solutions from FMUSER, hotels can stay ahead of the competition and exceed guest expectations.

Creating Healthier and Happier Guests with Hotel IPTV System
Are you looking for a solution that can enhance your hotel guest experience through wellness activities? Look no further than FMUSER’s IPTV solutions. Learn how in-room yoga sessions, meditation, and nutritional programs can promote healthier and happier guests.

Maximizing Revenue Opportunities and Improving Guest Experience with Hotel IPTV System
Discover how hotels can leverage the power of the hotel IPTV system for revenue management. This article explores the features, strategies, and benefits of personalized recommendations, targeted promotions, and in-room entertainment options that can enhance the guest experience and increase revenue.

Standing Out in the Crowd: The Advantages of Customizing Hotel IPTV System for Boutique Hotels
Discover how customizing IPTV systems can set boutique hotels apart by delivering tailored content and services that showcase their unique brand identity and ultimately enhance guest satisfaction.

Maximizing Online Reputation - The Link Between Hotel IPTV System and Positive Guest Reviews
Discover how hotels can improve their online reputation and attract more guests by using an IPTV system to provide an exceptional guest experience, resulting in positive reviews and higher ratings. Read our article to know more!

Leveraging Hotel IPTV Systems for Successful Hybrid Events & Conferences
Learn how hotels can use IPTV systems for live streaming, virtual conferences, and hybrid events. Explore the benefits of IPTV, revenue generation opportunities, and cost-effectiveness.

How Hotel IPTV Systems Can Attract Gen Z and Millennial Guests
With the rise of Gen Z and Millennial travelers, hotels are turning to hotel IPTV systems as an effective solution to attract younger guests. Discover how FMUSER’s hotel IPTV solutions can enhance the guest experience with social media integration, mobile app access, and advanced guest management tools.

Enhancing Hotel Safety and Security with IPTV Systems
Learn how hotels can use IPTV systems for enhanced surveillance, access control, and emergency management to create a safer and more secure environment for guests and employees. Explore the key features and benefits of IPTV systems, ways it can be customized to suit specific hotel needs, and advantages of investing in a quality IPTV system like the ones offered by FMUSER.

Contactless Check-In/Check-Out: Enhancing Guest Experience with Hotel IPTV System
Learn how hotels can use hotel IPTV system for contactless check-in/check-out to provide guests with a more efficient, enjoyable, and secure stay. With solutions from FMUSER, hotels can stay ahead of the competition and exceed guest expectations.

Creating Healthier and Happier Guests with Hotel IPTV System
Are you looking for a solution that can enhance your hotel guest experience through wellness activities? Look no further than FMUSER’s IPTV solutions. Learn how in-room yoga sessions, meditation, and nutritional programs can promote healthier and happier guests.

Maximizing Revenue Opportunities and Improving Guest Experience with Hotel IPTV System
Discover how hotels can leverage the power of the hotel IPTV system for revenue management. This article explores the features, strategies, and benefits of personalized recommendations, targeted promotions, and in-room entertainment options that can enhance the guest experience and increase revenue.

Streamlining Your Event Offering with Smart Hotel IPTV Systems
Discover how intelligent conference room hotel IPTV systems, such as those offered by FMUSER, can revolutionize the way you host conferences, meetings, and events. Featuring split-screen displays, video conference integration, and digital signage, our custom solutions will streamline your event offerings and create an unparalleled experience for all attendees.

The Future of Guest Comfort - Voice Control Enabled Hotel IPTV System
This article explores how voice control-enabled IPTV systems can enhance guests’ in-room experience in hotels. Learn about the benefits of voice control technology, best practices for its implementation, and how a leading provider like FMUSER can help hotels differentiate themselves.

Transforming the Guest Experience: Exploring the Future of IPTV in Hotels
Discover how IPTV solutions are revolutionizing the way hotels engage with their guests through personalized content, AI and IoT, and streamlined operations, driving profitability and customer loyalty.

The Future of IPTV Systems in Hospitality: Enhancing Guest Experience and Improving Efficiency
Discover how IPTV systems can benefit hoteliers by increasing revenue, streamlining operations, and improving customer satisfaction. Learn about FMUSER’s innovative IPTV solutions that cater to the growing demands of today’s guests.

The Top 7 Trends in Hotel IPTV Systems: Enhancing the Guest Experience
Stay ahead of the curve with the latest trends and technologies in hotel IPTV systems, including 4K resolution, personalized recommendations, interactive programming, multi-screen displays, and voice-activated controls. Learn how these innovative features can create a unique and engaging guest experience.

The Importance of Voice Integration in Future-Proofing the Hotel Guest Experience
Discover how voice integration can enhance hotel guest experiences and future-proof the hotel industry. Explore the importance of voice integration in hotel IPTV systems and how hotel solutions like FMUSER are leading the way in a competitive industry.

IPTV for Hotels: Bringing In-Room Entertainment to the Next Level
Discover how IPTV technology is reshaping the hospitality industry, including trends, innovations, and customized solutions for hotels and resorts.

The Evolution of IPTV in the Hotel Industry: Trends and Innovations You Should Know
Learn about the latest IPTV trends in the hotel industry, including cloud-based service, smart TVs, pay-per-view options, and mobile device integration. Read on to discover how FMUSER’s Hotel IPTV and Custom IPTV solutions can help you create a personalized and profitable entertainment experience for your guests.

The Future of Hotel Entertainment: 6 Innovations and Trends in IPTV Technology You Need to Know
Discover the latest innovations and trends in IPTV technology that will shape the future of hotel entertainment. Learn how hotels can leverage IPTV to offer an immersive in-room entertainment experience to their guests.

Standing Out in the Crowd: The Advantages of Customizing Hotel IPTV System for Boutique Hotels
Discover how customizing IPTV systems can set boutique hotels apart by delivering tailored content and services that showcase their unique brand identity and ultimately enhance guest satisfaction.

Maximizing Online Reputation - The Link Between Hotel IPTV System and Positive Guest Reviews
Discover how hotels can improve their online reputation and attract more guests by using an IPTV system to provide an exceptional guest experience, resulting in positive reviews and higher ratings. Read our article to know more!

Leveraging Hotel IPTV Systems for Successful Hybrid Events & Conferences
Learn how hotels can use IPTV systems for live streaming, virtual conferences, and hybrid events. Explore the benefits of IPTV, revenue generation opportunities, and cost-effectiveness.

How Hotel IPTV Systems Can Attract Gen Z and Millennial Guests
With the rise of Gen Z and Millennial travelers, hotels are turning to hotel IPTV systems as an effective solution to attract younger guests. Discover how FMUSER’s hotel IPTV solutions can enhance the guest experience with social media integration, mobile app access, and advanced guest management tools.

Enhancing Hotel Safety and Security with IPTV Systems
Learn how hotels can use IPTV systems for enhanced surveillance, access control, and emergency management to create a safer and more secure environment for guests and employees. Explore the key features and benefits of IPTV systems, ways it can be customized to suit specific hotel needs, and advantages of investing in a quality IPTV system like the ones offered by FMUSER.

Contactless Check-In/Check-Out: Enhancing Guest Experience with Hotel IPTV System
Learn how hotels can use hotel IPTV system for contactless check-in/check-out to provide guests with a more efficient, enjoyable, and secure stay. With solutions from FMUSER, hotels can stay ahead of the competition and exceed guest expectations.

Creating Healthier and Happier Guests with Hotel IPTV System
Are you looking for a solution that can enhance your hotel guest experience through wellness activities? Look no further than FMUSER’s IPTV solutions. Learn how in-room yoga sessions, meditation, and nutritional programs can promote healthier and happier guests.

Maximizing Revenue Opportunities and Improving Guest Experience with Hotel IPTV System
Discover how hotels can leverage the power of the hotel IPTV system for revenue management. This article explores the features, strategies, and benefits of personalized recommendations, targeted promotions, and in-room entertainment options that can enhance the guest experience and increase revenue.

Introduction: UHF TV Panel Antenna | FMUSER BROADCAST
Why the UHF TV panel antenna is so popular? Let's have a basic understanding of its features and applications. Let's explore it!

Top 3 Facts to Know about FM Radio Transmitters before Buying
How can I choose the FM radio transmitter that best meets my psychological expectations? I believe many people have thought about this question. This problem can be solved by remembering some important precautions before purchasing! This blog will briefly explain what an FM transmitter does, and focus on the three most important factors that need to be paid attention to before choosing a transmitter, namely quality assurance, frequency range, safety, to help those customers who want to buy FM transmitters to make a better choice! If this blog is helpful to you, don't forget to share this page!

What's The Best Commercial FM Radio Transmitter?
FM radio transmitter is the core of every commercial broadcasting company, because the purpose of the radio station is to cover a certain area and transmit the radio signal to every receiver, such as radio. FM transmitter is the electronic equipment that transmits radio signals.

Where to Buy Radio Broadcast Equipment at Low Prices?
Budget is an important factor that affects you to choose what kinds of Radio Broadcast Equipment. But usually, choosing a piece of low-price equipment indicates giving up the performance.

6 Best Buying Tips for Digital TV Transmitters at Low Cost
If you want to provide TV broadcasting services, a digital TV transmitter is a good choice for you. However, it is quite expensive. But FMUSER will provide 6 buying tips for you to reduce your costs.

6 Best Buying Tips for VHF TV Transmitters
VHF TV transmitter is still widely used in all around the world. To help you pick up the best VHF TV transmitter, we summarize 6 buying tips for the best one.

How to Choose the Best Analog TV Transmitter for Your TV Transmitter Station?
This blog would focus on how to choose the best analog TV transmitter, containing the basic introduction, how it works, the relative TV broadcasting equipment, and where to buy it.

How to Choose the Best Low Power FM Transmitter for Christmas Lights Display
Christmas Day is coming, do you have any idea of holding a Christmas light display? But How to choose the best low power FM transmitter for Chritsmas Light Display? Here's what you need.

FMUSER FU-1000C Low Costs Professional FM Broadcast Radio Transmitter
Are you troubled by the fact that your FM broadcast transmitter is not supporting you well in running your radio station? Why not try FU-1000C 1KW FM Transmitter, and it is the best low costs professional FM broadcast radio transmitter.

Notices Before Buying A FM Broadcast Transmitter
If you're a rookie who is looking for quality-assured FM broadcast equipment but not sure how to choose one, you'd better see this buying tutorial before making your final decision.

How Do Drive-in Church Serve In the Covide-19 Pandemic
What is the best way to attend the church service in 2020, the year of the covid-19 virus pandemic? Who and why need contactless services like the drive-in church? This article has all you need...

5 Useful Buying Tips for Drive-in FM Transmitter Antenna
With the epidemic breaking out, the drive in movie theater has gradually become one of the most popular forms of entertainment worldwide. It allows people to enjoy themselves with their family and friends safely. More and more people think that it is an excellent choice to start a drive in movie theater business.
The FM transmitter antennas are essential for starting a drive in movie theatre. Do you know how to choose the best FM transmitter antenna for dirve in movie theater? Luckily, we summarize 5 tips for choosing the best FM transmitter antenna for you. In addition, we would introduce some basic information about FM broadcast antennas to help you better understand them.
If you are eager for help in choosing the best FM broadcast antenna, this share is helpful for you. Let's keep reading!

4 Best Buying Tips for 100 Watt FM Transmitter
Today, with the epidemic becoming more and more serious, the drive-in movie theater is becoming more and more popular worldwide. It allows people to enjoy the movie time outside with friends and family without worrying about the risk of infection. Therefore, it is also a nice choice to start a drive-in movie business.
However, do you know how to choose the best FM transmitter for drive in movie? Luckily, to help you start your drive in movie business, we summarize the 4 main practical tips on choosing the best 100 watt FM transmitter for drive in movie. In addition, we also introduce what an FM radio transmitter is to help you have a better understanding of it.
If you are eager for help in choosing the best 100 watt FM transmitter, this share would be helpful for you. Let's keep reading!

Why You Must Have a FU-15A FM Broadcast Transmitter for the Drive-in Church?
Affected by COVID-19, the influence of new missionary methods such as car theaters, car churches, and remote prayer is gradually expanding in European and American countries. For the operators of churches and car theaters, how to attract large-scale traffic under the epidemic is the most important thing. Today FMUSER will introduce to you an ultra-low-budget FM transmitter suitable for high-quality broadcasting-FMUSER FU-15A

Why You Need A Good FM Transmittter in 2020?
How to let your customers safely use the car church and car theater services you provide? Good broadcasting equipment is essential. When you want a steady stream of traffic and the safest and highest quality broadcasting customer experience, this article will help you, let’s take a look!

FM Radio Transmitters Bring Movie Theatre and Church Back to the Cars
The COVID-19 affects all the countries in the world, and people have to comply with the hygiene and health rules, that keep social distance from others. But some broadcast equipment like FM transmitters for drive-in theatre makes pastors and audience are able to continue religious and entertainment events with low cost and convenience.

Covid-19 Broadcast: How FM Transmitter Serve in a Drive-in Church?
In some countries, the outbreak of covid-19 limited face-to-face contact church services, and many churches had to be temporarily closed. Fortunately, some drive-in church has successfully realized contactless FM church broadcasting services with FM radio transmitters. But do you know how FM radio transmitters serve the drive-in theater exactly? And for the church operator, how to choose a high-quality FM broadcast transmitter?

Startup Guide for a Drive Through Theater Buildup
Covid-19 has brought huge financial loss to the cinemas around the world, obviously it is also the main reason why most cinemas were shut down, so how do people entertain themselves in Covid era? How to earn great profits through the cinema customers? In this share, we will show you some interesting facts of drive through movie theater, including how to build up a drive through theater and few equipment needed such as a radio transmitter, antennas, etc.

8 Things Cannot Be Missed About Drive-In Movie Theaters
Are you tired of staying at home, and eager to have some fun? In this article, you will learn about how and why you should have a drive-in theater in these years, especially in the year 2020, which is also the year of the drive-in church, the year of the drive-in parking lot.

What FM Broadcasting Equipment Do You Need in Community Radio?
Community is an important form of broadcasting. You can get some idea of buying the fm broadcasting equipment for building up an FM station for community radio.

Studio Transmitter Link (STL Link) | What it is and How it Works
This blog will bring you how a studio transmitter link works, including the definition, types, and related equipment of STL link systems.

The Introduction to Studio Transmitter Link (STL)
Studio Transmitter Link (Studio Transmitter Link) is a unique wireless audio transmission technology in the broadcasting industry. The studio transmitter link, or studio to transmitter link, or Studio Transmitter Link link, can be divided into digital Studio transmitter link and analog studio transmitter link. Studio transmitter link equipment can be divided into equipment such as Studio Transmitter Link transmitter, Studio Transmitter Link receiver, and Studio Transmitter Link antenna, this varies from different types of studio transmitter links. Understanding the type and working principle of studio transmitter link can effectively reduce the expenses of purchasing equipment

Introduction: UHF TV Panel Antenna | FMUSER BROADCAST
Why the UHF TV panel antenna is so popular? Let's have a basic understanding of its features and applications. Let's explore it!

Where to Buy Radio Broadcast Equipment at Low Prices?
Budget is an important factor that affects you to choose what kinds of Radio Broadcast Equipment. But usually, choosing a piece of low-price equipment indicates giving up the performance.

How to Attach Several Televisions to One Antenna?
If you have multiple TVs in your house, as most of the people have you can develop, the connection of several Televisions with the very same exterior antenna. Making use of an antenna splitter appears to be a very easy way to establish a connection of numerous TVs with a single antenna.

6 Best Buying Tips for Digital TV Transmitters at Low Cost
If you want to provide TV broadcasting services, a digital TV transmitter is a good choice for you. However, it is quite expensive. But FMUSER will provide 6 buying tips for you to reduce your costs.

6 Best Buying Tips for VHF TV Transmitters
VHF TV transmitter is still widely used in all around the world. To help you pick up the best VHF TV transmitter, we summarize 6 buying tips for the best one.

Best Broadcast Equipment for a TV Transmitter Station
What's the best broadcast equipment for a TV transmitter station, especially the UHF TV transmitter and the UHF tv transmitter antenna? And how to choose them? This page would give you some ideas.

How to Choose the Best Analog TV Transmitter for Your TV Transmitter Station?
This blog would focus on how to choose the best analog TV transmitter, containing the basic introduction, how it works, the relative TV broadcasting equipment, and where to buy it.

Analog & Digital TV Transmitter | Definition&Difference
In the field of radio broadcasting, you can see that many devices use dipole antennas. It is not only the most widely used radio broadcast antenna, but also the simplest type of antenna. It can be used alone or combined with other FM antennas to form an antenna array.

Standing Out in the Crowd: The Advantages of Customizing Hotel IPTV System for Boutique Hotels
Discover how customizing IPTV systems can set boutique hotels apart by delivering tailored content and services that showcase their unique brand identity and ultimately enhance guest satisfaction.

Maximizing Online Reputation - The Link Between Hotel IPTV System and Positive Guest Reviews
Discover how hotels can improve their online reputation and attract more guests by using an IPTV system to provide an exceptional guest experience, resulting in positive reviews and higher ratings. Read our article to know more!

Leveraging Hotel IPTV Systems for Successful Hybrid Events & Conferences
Learn how hotels can use IPTV systems for live streaming, virtual conferences, and hybrid events. Explore the benefits of IPTV, revenue generation opportunities, and cost-effectiveness.

How Hotel IPTV Systems Can Attract Gen Z and Millennial Guests
With the rise of Gen Z and Millennial travelers, hotels are turning to hotel IPTV systems as an effective solution to attract younger guests. Discover how FMUSER’s hotel IPTV solutions can enhance the guest experience with social media integration, mobile app access, and advanced guest management tools.

Enhancing Hotel Safety and Security with IPTV Systems
Learn how hotels can use IPTV systems for enhanced surveillance, access control, and emergency management to create a safer and more secure environment for guests and employees. Explore the key features and benefits of IPTV systems, ways it can be customized to suit specific hotel needs, and advantages of investing in a quality IPTV system like the ones offered by FMUSER.

Contactless Check-In/Check-Out: Enhancing Guest Experience with Hotel IPTV System
Learn how hotels can use hotel IPTV system for contactless check-in/check-out to provide guests with a more efficient, enjoyable, and secure stay. With solutions from FMUSER, hotels can stay ahead of the competition and exceed guest expectations.

Creating Healthier and Happier Guests with Hotel IPTV System
Are you looking for a solution that can enhance your hotel guest experience through wellness activities? Look no further than FMUSER’s IPTV solutions. Learn how in-room yoga sessions, meditation, and nutritional programs can promote healthier and happier guests.

Maximizing Revenue Opportunities and Improving Guest Experience with Hotel IPTV System
Discover how hotels can leverage the power of the hotel IPTV system for revenue management. This article explores the features, strategies, and benefits of personalized recommendations, targeted promotions, and in-room entertainment options that can enhance the guest experience and increase revenue.
What people say?

Tommy
FMUSER has great pre-sales and after-sales services. When I first consulted FMUSER’s sales staff about their FM radio products, they patiently guided me on how to choose the professional FM radio equipment that suits me. When I bought After a 150W FM transmitter, they patiently answered various difficult questions. Thank you FMUSER!

Hayward
The reason why I like to buy FM radio products from FMUSER is that they have a very large variety of products. I thought it was a small company only selling FM radio transmitters, but they even sold encoding equipment for live broadcasting, which is one of the hottest and mainstream entertainment methods of these years, so cool! And the price is very reasonable, the quality is also good as well, looking forward to the next shopping!

Randy
I bought a complete studio set from FMUSER. It is perfect and the price is relatively affordable. Compared with similar domestic broadcast equipment sets, FMUSER’s broadcast set is very satisfactory, I can even say this is one of the best shopping feelings ever. You only need to fill in the "technical support" form and contact their technician, then you can be free from the issues of machine breaking down, thank you, FMUSER!
7 DAYS to customize the best radio station coverage solution for you.
Why 7 DAYS is all enough?
For we have 4 RF FACTORIES as well as 20+ PRODUCT EXPERTS with 10+ YEARS of experience in radio station design and coverage who will always have your back.
Ask For Quote Now!
WE WILL REPLY WITHIN 24 HOURS.
We escort your privacy - Your private information will be kept strictly confidential by FMUSER.
CONTACT US


FMUSER INTERNATIONAL GROUP LIMITED.
We are always providing our customers with reliable products and considerate services.
If you would like to keep touch with us directly, please go to contact us