303

A silver oxide button cell in the SR44 footprint. The 303 code marks the low-drain variant sold for watches.

All button cells
Voltage
1.55 V
Chemistry
Silver Oxide
Size
11.6 × 5.4 mm
Capacity
150–175 mAh

Specifications

Specifications for the 303 battery
TypeButton Cell
ChemistrySilver Oxide
Nominal voltage1.55 V
Diameter11.6 mm
Height5.4 mm
Typical capacity150–175 mAh
RechargeableNo
Also sold asSR44SW, D303, V303

Equivalent batteries

These codes describe the same physical cell as the 303.

SR44SWDirect
Same cell, different code
SR44Direct
Silver Oxide · 1.55 V

Can I replace 303 with…

Cells that fit the same space but differ in chemistry or voltage.

3571.55 V

Silver Oxide, 11.6 × 5.4 mm. Same footprint — it will physically fit.

LR441.5 V

Alkaline, 11.6 × 5.4 mm. Same footprint — it will physically fit.

Check before you swap. Batteries with similar dimensions are not always interchangeable with the 303. Always verify voltage, chemistry and the requirements printed in your device manual before fitting a replacement.

303 questions

What batteries are equivalent to the 303?

The 303 is sold as SR44SW, SR44. All of these describe the same 11.6 × 5.4 mm silver oxide cell at 1.55 V.

Can I use a 357 instead of a 303?

In many low-drain devices, yes — the sizes match. Check the voltage and chemistry against your device's requirement first, because a small voltage difference can matter in calibrated equipment.

How long does a 303 last?

A 303 holds a typical 150–175 mAh. Real runtime depends entirely on how much current your device draws and whether it is used continuously.

Is the 303 rechargeable?

No. The 303 is a single-use cell and should not be recharged.