HK Waterproof Bluetooth Fitness Tracker Bracelet Smart Wrist Watch Band for iPhone Android w/Touch Screen &hellip; Smart Touch Screen Wireless Fitness Tracker for iphone Android Size: screen: 0.91"/ Working time: 120 to 168 hours Waterproof Level: IP64 waterproof; Can't be submerged in water System requirement: Android 4.4 and above, IOS 8.0 and above, with Bluetooth 4.0