An AAA or triple-A battery is a standard size of dry cell battery commonly used in low drain portable electronic devices. A carbon-zinc battery in this size is designated by IEC as "R03", by ANSI C18.1 as "24", by old JIS standard as "UM 4", and by other manufacturer and national standard designations that vary depending on the cell chemistry.
A triple-A battery is a single cell and measures 44.5 mm in length and 10.5 mm in diameter. The length includes the positive terminal button which is a minimum 0.8 mm high and 3.8 mm in diameter; the flat negative terminal has a minimum diameter of 4.3 mm.[1] Alkaline AAA batteries weigh around 11.5 grams each, while primary lithium AAA Batteries weigh about 7.6 g. Rechargeable nickel–metal hydride (NiMH) AAA Batteries typically weigh 14–15 g.