[ Boardcom US Bluetooth 5.1 Chipset]-Low latency and stable performance,an assurance for high quality keyboard. [ Ultra Big Touchpad with Left&Right Click]-Maximumly approach the user experience of laptop touchpad. [ 3 Channels Bluetooth Connection] -3 bluetooth device can connect with the folding keyboard and switch between each other randomly. [ Big Size Keycap&Scissors Switch] -1:1 keycap size &layout as laptop and comfortable scissors switch. [ Rechargeable Lithium Battery] -Build in 210mAh big capacity rechargeable lithium battery,long standby time and environment friendly. [ Multi System Compatible] -Compatible with Windows,Android,IOS and Mac(Desk,lock key can not use),fully satisfy your of input requirement. [ Textured PU Leather Back Cover] -Nice hand feeling and business style. [ Tri-Folding Keyboard] -Combine the nice input user experience of standard size keyboard and portable mini size advantage into one keyboard. Multi-channel connection Manual When connecting the first device, first press "Fn+ BTi" and then press"Fn+C "to start the connection. *Before connecting the second device, press "Fn+ BT2 "once, then press" Fn+C "to start the connection..Before connecting the third device, press "Fn+ BT3" once, then press"Fn+C" lo slart the connection. *To use multiple devices at the same time, press Fn + BT1 / BT2 BT3 to switch to the connected devices freely