377/376 (SR66) Watch Batteries

The 377/376 button cell is a popular manufacturer’s choice of batteries for watches, calculators, toys and talking children’s books. These cells replace both alkaline and silver oxide cells with the names SR66, LR66, AG4, SG4 and SR626SW.

These 1.55V batteries are based on silver oxide chemistry. They typically provide about 26mAh of capacity. The case dimensions are 6.8mm x 2.6mm.