Product information:
Watch band material: silicone watch band
Bluetooth: Bluetooth 5.0
Shell material: zinc alloy+plastic
Operation mode: multi-touch+physical keys
Battery capacity: 220mAh
Color: black, gold, pink
Display: 1.72-inch square color screen resolution 240 * 280
Charging method: magnetic charge
Charging specification: charging 1A or less
Charging time: 2 hours
Waterproof grade: IP67
Compatible platform: IOS 8.0 Android 4.4 or above

Packing list: 

NK21 bracelet, manual, connecting small card, packing box