cnBro Smart Ring - LED Screen Heart Rate Monitor Sleep Tracker

MULTIFUNCTIONS: - Remote Mobile Phone Camera - Pedometer:Steps,Calories,Distance - Heart Rate Monitor - Sport Modes - Sleep Tracker HARDWARE: Bluetooth:5.0 Charging Type:Magnetic Charging Full Charge Time:About 1-2 Hour Ring Battery:20mAh APP:Smart Health Standby Time:One full charge gives you(3-5 days of working time) iOS 8.0 or above,Android 5.1 or above Ring Material:Carbon Fiber Packaging Accessories: Smart Ring*1 Charger*1 Manual RING SIZE: US7 (Ring inner diameter:17.3mm/0.68",Ring circumference:54.3mm/2.14") US8 (Ring inner diameter:18.1mm/0.71",Ring circumference:56.9mm/2.24") US9 (Ring inner diameter:18.9mm/0.74",Ring circumference:59.5mm/2.34") US10 (Ring inner diameter:19.8mm/0.78",Ring circumference:62.1mm/2.44") US11 (Ring inner diameter:20.6mm/0.81",Ring circumference:64.6mm/2.54") US12 (Ring inner diameter:21.4mm/0.84",Ring circumference:67.2mm/2.64") US13 (Ring inner diameter:22.2mm/0.87",Ring circumference:69.7mm/2.74") Weight:4g - IP68 Waterproof - DO NOT suitable for hot water bathing,diving,water-related work. Any questions,please kindly contact us,we would always offer best solution to you.