Product details of Amazfit Bip Smartwatch 30+ DAYS OF BATTERY NOTIFICATION LIGHTWEIGHT MULTISPORT TRACKING ALWAYS-ON DISPLAY GPS HYPOALLERGENIC Always-on reflective 1.28 inch color touch display 2.5D Corning gorilla glass generation 3 + AF coating Optical heart rate sensor for heart rate zones Geomagnetic sensor (compass) Air pressure sensor (barometer) for elevation GPS + GLONASS for route tracking 20 mm standard width changeable watch band IP68 rating - resistant to dust, rain and splashing 190mAh Li-Polymer Battery 1.1 ounces (31 grams) total weight