Battery size: 4SR44. Type: Silver oxide. Other designations: 544, PX28, V28PX, A544, 4NZ-13, 4G13, KS28, 4LR44. : 25.2 x 13 mm. Weight (of one battery): 14 g (0.03 lbs). Made in Japan. 100% authentic, original Panasonic product.
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