<br><b>Main Specifications</b> <br>Bracelet Chipset: MXD2657B <br>Heart Rate Sensor：Tianyihexin/HRS3300 <br>Bracelet Weight: 35g <br>Data Connection: BT 5.0 <br>Battery Type: Li-lithium <br>Bracelet Battery Capacity: 110mAh <br>Charging Voltage：5V <br>Charging Current: 80mA <br>Working Temperature: -5～45℃ <br>Waterproof: No <br>Compatible O.S: Android5.0 or above, Smart device BT 5.0iOS 8.0 or above