AmazFit GTR A1902 Amazfit GTR 47mm Size 47.2 x 47.2 x 10.75 mm Weight (without strap) Aluminum alloy：Approx. 36g Stainless steel：Approx. 48g Titanium：Approx. 40g Water & Dust Resistance Grade 5 ATM Screen 1.39" AMOLED, Resolution 454x454, 326 ppi Touch Screen Corning Gorilla 3 tempered glass + Anti-fingerprint coating Types of Standard Watch Straps Aluminum alloy: Brown leather strap Stainless steel: Brown leather strap Titanium: Fluororubber strap Strap Width 22 mm Sensors BioTrackerTM PPG biological tracking optical sensor, 6-axis acceleration sensor, 3-axis geomagnetic sensor, Air-pressure sensor, Capacity sensor, Ambient light sensor Positioning GPS+GLONASS Connectivity BT5.0 BLE Battery 410mAh LiPo Charging Method Magnetic charging base, 2Pin Pogo Pin charging Theoretical Charging Duration Approx. 2 hours Battery Life Typical usage scenario: 24 days Heart rate always on, sleep monitoring, 150 pushed notifications with screen light-up, lift the wrist to see the screen 30 times, run or exercise 3 times a week for 30 minutes with GPS on, and 5 minutes for other operations. Basic watch mode: 74 days Turn off Bluetooth, heart rate, and other features, and raise your wrist to see the screen 100 times a day. Body Materials Metal, microcrystalline zirconium ceramics, polymer materials Supported Devices Android 5.0 and above, iOS 10.0 and above Accessories Magnetic charging base, user manual App Zepp App (formerly known as the Amazfit App) الحالة جديد الماركة ماركة أخرى