Material: ABS+ iron backboard Tablet size: 7 9.7 inches System: for Android system, apple IOS system, Microsoft windows system. Bluetooth solution: for American Broadcom Bluetooth version: 3.0 Bluetooth distance: 0-10 meters (unimpeded) Bluetooth Name: Bluetooth 3.0 Keyboard Battery: rechargeable lithium battery Lithium battery capacity: 110mA Battery life: 3 years Charging time: <2 hours Charge current: more than 100mA Sleep current: <40UA Use time: 4-5 days Standby time: >30 days Standby current: 0.3 ~ 0.5mA Working voltage: 1.8 ~ 3.6V Working current: < 4.0mA