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Home › Batteries › 344
Watch battery

344 is the same as SR42

1What it is2Safety3Other names4Facts5Buy it
  1. 1

    What it is

    SR42+ 1.55V

    344 is just another name for SR42. Same battery, different label, so you can buy either one.

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  2. 2

    Safety first

    Keep away from children and pets

    A swallowed coin or button battery can cause serious burns inside the body within 2 hours. If you think one was swallowed, get emergency help right away.

    Swallowed one? What to do now →
  3. 3

    Names you might see in the store

    All of these are the same battery. Any of them will work.

    SR42SR1136SR1136S350387S242D344V344
  4. 4

    Quick facts

    Size
    About as wide as a shirt button
    Thickness
    As thick as 5 credit cards stacked
    Power
    1.55 volts
    Keeps in a drawer for
    About 5 years
    Rechargeable?
    No, use once
    Found in things like
    Analog watchesCalculatorsMedical devices
  5. 5

    Where to buy it

    As an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

    Amazon searchEnergizer listings, any pack sizeSearch Amazon for Energizer 344
    See results on Amazon →
    Amazon searchMulti-packs from any brandSearch Amazon for 344 (SR42) multi-packs
    See results on Amazon →
    Amazon searchDuracell D344 listings, the same batterySearch Amazon for Duracell D344
    See results on Amazon →

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See it at real size

SR42 next to a US quarter and an AA battery. “Real size” matches your hand once your screen is set up in Measure it.

SR42Thickness 3.6US quarterAA

What do the letters mean?

Battery names are a code. Here’s how to read 344:

3Watch-industry 300 series (Renata/Energizer numbering)
44Size and drain code. Maps to SR42, 11.6 × 3.6 mm

The same battery from each brand

BrandTheir name for it
Official nameSR42
Energizer344
DuracellD344
Renata (Swiss)344
VartaV344
MaxellSR1136SW

Exact measurements

Width
11.6 mm (0.457 in)
Thickness
3.6 mm
Voltage
1.55V (empty at 1.2V)
Energy stored
100 mAh
Weight
—
Made with
Silver oxide
Works between
-10 … 60 °C
Official code
SR42 · ANSI 1139SO

Questions people ask

Is 344 the same as SR42?

Yes. They’re the same battery with different names. You might also see SR42, SR1136, SR1136S, 350.

How long will a spare keep in a drawer?

About 5 years if it stays cool and dry.

Can I recharge it?

No. Never try to recharge it.

Which way up does it go?

Usually with the side marked “+” facing you or facing up. Look at how the old one sits before you take it out.

SR42+ 1.55V
SR42Watch battery
Search Amazon for 344As an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

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1What it is2Safety3Other names4Facts5Buy it