LR416, SR416, SR416SW, SR416S, 337 Battery Equivalents, and Replacements
SR416SW or 337 battery is a popular, low-drain wristwatch battery used for powering other small devices, too, that requires a compact, but stable power source.
Other common labels are SR416, LR416, SR416S, and similar. Note: LR416 features alkaline chemistry and is rarely used for quartz watches and other small devices.
SR416SW/337 Battery Features and Specifications
SR416SW/337 battery is a silver-oxide button/coin-cell battery commonly used in low-drain devices.
Its physical dimensions (DxH) are 4.8 x 1.6 mm (0.1889 x 0.063 inches) and on average it weighs just ~0.12 grams.
The nominal voltage of the silver-oxide SR416SW/337 battery is 1.55 volts, with a cut-off voltage of 1.2 volts and a capacity of ~8 mAh.
For example, the Maxell SR416SW battery features a nominal capacity of 8.3 mAh when being drained with a discharge current of 10 μA.
Because of its tiny dimensions, SR416SW is used for credit card-sized devices and watches without alarms and backlit display - they are that tiny.
The nominal voltage of the alkaline LR416 battery is 1.5 volts, with a cut-off voltage of 0.9-1.0 volts and a capacity of ~5 mAh.
Since silver-oxide chemistry features more stable output voltage, longer shelflife, and larger capacity, silver-oxide SR416SW batteries are much more common, with alkaline LR416 being almost completely phased out.
SR416SW/337 Battery Safety Issues
SR416SW/337 is a very small battery that can easily get swallowed by kids and/or pets.
Although its capacity is rather low, it can still cause burns due to the electrolytic reactions with body fluids.
So, don't leave SR416SW/337 or any similar battery near pets and kids - fortunately, most of these batteries come in so-called kids/pet safe packaging, preventing them from swallowing them.
However, if that happens, contact the emergency services and act as advised.
Long Story Short: If You are looking for a silver-oxide 4.8x1.6 mm button/coin-cell battery, go for batteries labeled as LR416, SR416, SR416SW, SR416S, and/or 337 from reputable brands.
These batteries are small and thus not expensive, but the batteries from such brands usually feature longer shelflife, larger capacity, longer runtime, etc.