EPX76 : 1.5 volt silver oxide button battery. Size is 11.2mm dia x 5.2mm tall. X-ref #s are LT1154, CR44, SR44, 357A, SR44W, AG13, G13, A76, A-76, PX76, 675, 1166a, LR44H, V13GA, GP76A, L1154, RW82B, EPX76, SR44SW, 303, SR44, S303, S357, SP303, SR44SW.
This non-rechargeable battery is often found in various calculators, cameras, watches, pedometers, keychain lights, toy lasers, and other low-drain electronic devices.