F21 GPS Smart Bracelet Cardio Heart Rate Blood Pressure Watch IP68 Waterproof Smart Band Calorie Pedometer Sports Bracelet Main functions: Heart rate: support Blood pressure: support Sleep monitoring: support Sedentary reminder: support Female physiological period function reminder: support Time display, step Traker, calories, distance, stopwatch , countdown call reminder, reminder message reminder alarm, anti-lost reminder, camera remote control, lifting them to brighten their hand Description: Product model: F21 App operating system: For IOS 8.0 or above, for Android 4.4 or above Gsencor sensor: KXTJ3-1057 Master: nRF 52832 Heart rate sensor: Yiguang PD70-01C-TR7 Vibration reminder : motor vibration reminder Waterproof Rating: IP68 Display: 1.14 ""135 * 240 resolution TFT Blue tooth: BLE 4.0 Strap material: silicone band Host size: about 47 * 24 * 13mm / 1.85 * 0.94 * 0.51 inch Machine size: about 260 * 24 * 13mm /10.24*0.94*0.51 inch Operation: single-touch, lift the wrist screen will be bright.Battery : polymer lithium-ion battery Battery capacity: 100mAh Standby time: 7-10 days Charging method: magnetic charging cable Charging time: approx. 2 hours Supported languages: Chinese, English, German, Russian, Japanese, French, Korean, Portuguese, Spanish, Italian, Persian, Vietnamese.