Leader 377 Watch Batteries are precision silver oxide button cells engineered to deliver dependable, extended power to watches and compact electronic devices. The silver oxide chemistry maintains stable 1.55V output throughout the battery's lifespan, ensuring accurate timekeeping until complete discharge. These versatile cells are compatible with multiple device types including analog watches, medical instruments, and small electronics. Also recognized as SR626SW, SR66, or AG4, this standardized size offers broad compatibility across numerous applications. Advanced sealing technology provides robust leak-resistant protection, safeguarding sensitive internal components from corrosive damage. The durable construction ensures reliable performance in precision instruments requiring consistent voltage stability. This 4-count pack delivers economical bulk value for households maintaining multiple watches or devices requiring frequent battery replacements, combining quality silver oxide chemistry with practical affordability.