Stainless Steel & Mud-resistant Design: Constructed with super-strong 316L stainless steel and a patented mud-resistant bridge and buttons, Amazfit T-Rex Ultra is built to withstand any kind of action. The smartwatch's HD AMOLED display can reach a peak brightness of 1,000 nits for ultra-clear visibility in any environment. Adjustable lugs ensure maximum comfort for the entirety of your epic adventures, and you can enjoy ultimate control with a responsive touchscreen and four convenient buttons. 30m Freediving Support: As the ultimate multi-environment outdoor smartwatch, the Amazfit T-Rex Ultra supports indoor and outdoor freediving to a depth of up to 30 meters. It can also resist the equivalent of up to 100 meters’ water pressure, making it perfect for all your swimming, surfing and kitesurfing activities. Dual-band GPS & Route Navigation: The smartwatch utilizes both L1 and L5 signals for incredibly precise dual-band GPS positioning, and supports six satellite systems for greater global coverage. Import a route file to the watch along with a corresponding Offline Map, and navigate with professional-level environmental understanding. Mighty 20-day Battery Life: Experience energy beyond extinction, with battery life that can last a super-long 20 days. The sports watch also introduces a new Endurance GPS battery mode for those who love to lose themselves in nature for long periods of time, plus a new Automatic GPS battery mode which intelligently adjusts GPS settings based on signal strength, to help conserve power. -30℃ Ultra-low Temperature Operation: Built for the brave, the watch is tough enough to be operated in extreme temperatures as low as -30℃, thanks to its specially designed circuitry system and battery. So not only can the watch body physically resist the cold, but you can keep using the watch's functions as the conditions get more intense. Military-grade Toughness: Resistant to extreme 70℃ heat and -40℃ cold - as well as humidity, shock and more - this outdoor smartwatch has proved its toughness by passing 15 military-grade tests. Understand your surroundings better with the built-in compass and barometer, along with environmental reminders and a host of other useful features. Sync To Your Favorite Health Apps: Share completed routes and activity data from your legendary adventures with fitness communities like Strava, adidas Running, Komoot and Relive, along with smartphone apps like Apple Health and Google Fit. Ready for Action Shots: Thanks to the powerful Bluetooth connectivity the Amazfit T-Rex Ultra supports music playback, heart rate belts and cycling power meters and can even connect to your GoPro action camera. Connection: WLAN 2.4GHz, Bluetooth 5.0 BLE. Prepared for Any Adventure: Brave your journey with the T-Rex Ultra smartwatch adventure features including - Compass, Air Pressure, Altitude, Altitude SpO₂, Sunrise / Sunset, Ocean Tides, Storm Warning Alerts, and Freediving Water Temperature Supported Devices: Compatible with Android 7.0 and above, iOS 12.0 and above devices.