PLEASE READ: To register, turn off your VPN (iPhone users- disable iCloud); you can re-enable the VPN after registration. You must maintain an active email address on your account: disposable email addresses cannot be used to register.
Depends on the batteries you use and how long you use them for and a whole bunch of other stuff.
I change the batteries in my mouse about four times a year. In the keyboard it is a lot less, maybe twice a year.
