A card of four Energizer MAX AA batteries. Energizer MAX alkaline batteries are general-purpose 1.5 V single-use cells for everyday devices such as torches, clocks, radios, remote controls, smoke detectors, toys and computer mice. Energizer's Power Seal technology locks the power in so the cells hold their charge in storage and the pack states up to 10 years' shelf life. The AA size (E91 / LR6 / penlight) is about 14.5 mm across and 50 mm long, the standard size for most torches, wall clocks, game controllers and remotes. The cells are designed not to leak in normal use and are marked up to four times longer lasting than carbon zinc batteries. A four-pack covers most devices that take two or four AA cells in one go.