Battery size: LR1. Type: Alkaline. Other designations: 4001, AM5, E90, KN, LADY, LR1, MN9100, MN9100/N, N, UM-5, UM5, LR01, KN-2, 810, 910A, LR1-N, LR1/E90. Weight (of one battery): 12 g (0.026 lbs).
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