The Xiaomi Mi Band 3 is a wearable activity tracker produced by Xiaomi Inc. It was released on 31 May 2018. It has a capacitive OLED display. The tracker features heart rate monitoring, although it does not offer continuous heart rate display.Specifications:Display: 0.78 inch OLED, single point touch screen.Resolution: 128 x 80 pixels.Button: capacitive.Connectivity: Bluetooth version 4.2 BLE; NFC on some models.Size: 46.9 x 17.9 x 12 mm.Weight: 20 g.Casing: plastic + alloy.Battery capacity: 110 mAh for 20 days of battery life.Sensors: accelerometer, optical heart rate monitor.SoC: Dialog Semiconductors 14681[3], clock rate 32 kHz up to 96 MHz.Waterproof: up to 50 metres, 5 atmospheres.