Specification:Number of key caps: 81 keysKey working current: < 4mAStandby current: < 0.65mATouchpad working current: 15mASleep current: 27μANet weight of keyboard: About 275gLithium battery capacity: 140mAhWorking distance: 10mAwaken way: Press keyWorking voltage: 3.7 VCharger specifications: 5V 1A or 2ASleep time: Ten minutesStandby Time: 90 DaysUninterrupted Working Time: 35HSystem support:Win/Android/IOS/OS/HMSOpen Size: About 304.1*216*6.1mmFolded Size: About 152.4*100*19.8mmTouch panel size: About 132 * 61mmMulti-channel Connection:When connecting the first device, first press Fn+1 and then press Fn+C to start the connection.Before connecting the second device, press Fn+2 once, then press Fn+C to start the connection.Before connecting the third device, press Fn+3 once, then press Fn+C to start the connection.To use multiple devices at the same time, press Fn +1/ 2/ 3 to switch to the connected devices freely .