At One Place

SR43 battery

What replaces a SR43
386, 301, SR1142, SR43W, SR43SW, D386
1.55 V silver oxide, 11.6 × 4.2 mm (diameter × height)

The SR43 is a single-use 1.55 V silver oxide button cell. The codes below are the same physical cell sold under different manufacturer names, and any of them will fit.

Specification

IEC designation
SR43
ANSI / NEDA
1133SO
Nominal voltage
1.55 V
Chemistry
Silver oxide
Size
11.6 × 4.2 mm (diameter × height)
Typical capacity
120 mAh
Rechargeable
No — never charge it

Codes that mean the same battery

Different manufacturers, one physical battery. Voltage, chemistry and dimensions all match.
Code Fits?
386 Yes — same cell
301 Yes — same cell
SR1142 Yes — same cell
SR43W Yes — same cell
SR43SW Yes — same cell
D386 Yes — same cell
V386 Yes — same cell
1133SO Yes — same cell
SB-A8 Yes — same cell
MS76H Yes — same cell

Codes that look close but are not

Code Why it is not a substitute
LR43 / 186 / AG12 Alkaline in the same can: 1.5 V, sloping, 123 mAh. Same physical fit, different voltage behaviour.
SR44 / 357 Same diameter, 1.2 mm taller. It will not close an SR43 compartment.

The SR43 is a primary cell and must never be put in a charger. Charging a sealed primary battery builds gas pressure inside a can with no vent designed for it, which is how they rupture or catch fire. Rechargeable look-alikes exist for several sizes and carry different codes — check the code, not the shape.

Where it turns up

  • Vintage camera meters via an MR-9 voltage adapter
  • Older quartz watches
  • Medical and dental instruments
  • Small electronic test gear

The cell that goes inside an MR-9 adapter to replace a PX625 mercury cell: the adapter drops its 1.55 V to the 1.35 V a vintage light meter expects.

Common questions

What is equivalent to a SR43?
386, 301, SR1142, SR43W, SR43SW, D386, V386, 1133SO, SB-A8, MS76H — all the same 1.55 V cell under different manufacturer codes.
Can I use a LR43 / 186 / AG12 instead of a SR43?
Alkaline in the same can: 1.5 V, sloping, 123 mAh. Same physical fit, different voltage behaviour.
Is the SR43 rechargeable?
No. It is a primary cell — charging one risks rupture or fire. Rechargeable look-alikes exist in the same size under different codes.

Related pages

Sources

  1. Official vendor product documentation — At One Place

How these figures are compiled and checked