A triple A or AAA battery is a standard size of dry cell battery commonly used in 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. Alkaline AAA batteries weigh around 11.5 grams each, while lithium AAAs weigh about 7.6 g. Rechargeable nickel–metal hydride (NiMH) AAAs typically weigh 14–15 g.
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