AAAA battery

batteries The AAAA battery (usually read as quadruple-A) is 42.5 mm long and 8.3 mm in diameter. The alkaline cell weighs around 6.5 g and produces 1.5 V. This size battery is also classified as R8D425 (IEC) and 25 (ANSI/NEDA). The alkaline battery in this size is also known by Duracell type number MN2500 or MX2500 and Energizer type number E96.
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