AA batteries (LR6)
Remote, alarm clock, toy or wireless mouse: alkaline and zinc-carbon AA batteries by Duracell, Varta, Kodak, Camelion. Stock up.
The AA cell, called LR6 in alkaline and R6 in zinc-carbon, is the most common size: 1.5 V and 14.5 mm across. Alkaline lasts longer in power-hungry devices such as toys and game controllers. Zinc-carbon is enough for a remote or a wall clock. Varta, Kodak and Duracell are alkaline, Camelion comes in both.