AG4 and LR626 are usually the same physical size as 377 / SR626SW, but they are alkaline cells. For most watches, a silver oxide 377 or SR626SW is the better replacement because voltage stays more stable.

LR44 is alkaline and SR44 is silver oxide. They are normally the same physical size, but SR44 is often preferred for watches and instruments because it gives steadier voltage and longer service.

SW cells are usually low-drain silver oxide cells for standard analogue watches. W cells are usually higher-drain versions for watches with extra features. If the old battery says W, use the W version where possible.

No. Solar, kinetic and Eco-Drive watches normally need a rechargeable cell or capacitor pack. A normal disposable silver oxide or lithium battery can damage the charging circuit or fail quickly.

No. CTL1616 is rechargeable and is used in many Casio solar watches. CR1616 is a disposable primary lithium cell and should not be used as a substitute unless the watch manufacturer specifically states it.

Use calipers to measure the diameter across the round face and the height or thickness of the cell in millimetres. Match both measurements before fitting a replacement.

Yes. 377 is the common trade number and SR626SW is the IEC-style code for the same 6.8 mm x 2.6 mm silver oxide watch battery.

Yes. 371 and SR920SW refer to the same common 9.5 mm x 2.05 mm low-drain silver oxide watch cell. AG6 or LR920 may be the same size but are alkaline alternatives.

Yes. 395 and SR927SW are the same 9.5 mm x 2.7 mm low-drain silver oxide cell. The high-drain version in the same size is often marked 399 or SR927W.

SR normally means a silver oxide button cell. Silver oxide cells are commonly used in watches because they hold a stable voltage during most of their life.

LR normally means an alkaline button cell. Some LR cells are the same physical size as silver oxide watch cells, but they usually have a less stable voltage and shorter service life in watches.

No. Seiko Kinetic rechargeable cells can use different part numbers and connector shapes, such as 3023 24R, 3023 44Z or 3023 5MZ. Match the movement calibre and original connector before ordering.

No. Citizen Eco-Drive cells use different 295 part numbers, such as 295-56, 295-51 and 295-33. The correct part depends on the movement calibre.

Usually no. ML cells are rechargeable, while CR cells are disposable primary lithium cells. They may look similar, but they are not the same for solar or rechargeable watch circuits.

Casio module numbers are usually printed in a small box on the case back. Searching the module number can be more reliable than searching only the model name.