399/ SR927W
Maxell Watch Battery SR927W is a silver oxide high drain battery 1.55 V. Watch Battery SR927W measures 9.5 x 2.7mm. It is mercury free and has a capacity of 55 mAh.
Interchange: Energizer 399, Renata 399, Varta V399, Rayovac 399, Duracell D395/399, Timex W, Citizen 280-44, Seiko SB-BP, I.E.C SR927 (SR57)