[Military Standard Toughness] with 15 Military Certified (MIL-STD-810), T-Rex Pro can withstand extreme temperatures and conditions: 70 C Heat / -40 C Cold / 240 hours Humidity / 96 hours Salt spray.[100+ SPORTS MODES & 10 ATM Water Resistance] T-Rex Pro offers over 100 exercise modes, like running, treadmill, trail run, walking, elliptical, climbing, hike, skiing, indoor cycling, swimming, etc. It is 10 ATM certified, meaning it's water resistant to up to 100 metres in depth and capable of tracking your movements even under water.[High-precision navigation] Equipped with quad-GNSS (GPS, GLONASS, BeiDou, Galileo), T-Rex Pro will be a reliable companion in the most challenging environments.[All-round Health Tracking] Equipped with self-developed BioTracker 2nd generation PPG biological optical sensor, T-Rex Pro can monitor your real-time heart rate, blood oxygen saturation, sleep quality, stress level, etc.[Ultra-long 18-day Battery Life] T-Rex Pro is equipped with a powerful 390mAh battery that can last up-to 18 days. Its ready to go where you go.