Manufacturers will label their batteries with a W to indicate they are for watch usage (silver oxide).

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Accurist, Casio, Fossil, Seiko, and Timex all employ the Energizer 377/376 SR626SW button cell in their timepieces. But, some manufacturers label AG4 (incorrect) and silver-oxide batteries with both SG4 (correct) to indicate that they are a substitute for SR626SW/SR626/LR626/SR66/LR66/SG4/AG4 batteries. Hearing aids, diabetes meters, blood pressure monitors, calculators, and watches and a variety of other electronic devices are all compatible with the Energizer 376 battery.However, most manufacturers now offer SR626 batteries (multi-drain) that may be used in keychain LED torches, thermometers, analog watches, both digital and toys, and other devices. Seiko V377, SR66, GP377, SR626SW, SR626, SB-AW, Citizen 280-39, D377, 565, BA, Bulova 606 are some of the other names for this watch.

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LR626 batteries are also known as AG4 batteries, LR66 batteries, alkaline 376 batteries, alkaline 377 batteries, and others. Batteries made in the last several decades have not used mercury or cadmium or dangerous and unstable heavy metals. To add to the confusion, some manufacturers use different names for both batteries, such as SG4, 376, 377, GA4, AG4, SR66, LR66 and so on.

A sodium hydroxide electrolyte battery is identified by the letter ‘S’ in the battery code following the digits. A potassium hydroxide battery is identified by the letter ‘P’ in the battery code following the digits. Furthermore, such batteries hold a higher capacity, allowing for a significantly longer operation duration for several devices with just one battery replacement. If the battery code begins with the letter ‘S,’ the coin cell is a’silver-oxide’ kind (SR626, SR66, SR626SW).