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Home › Batteries › 309
Watch battery

309 is the same as SR754SW

1What it is2Safety3Other names4Facts5Buy it
  1. 1

    What it is

    SR754SW+ 1.55V

    309 is just another name for SR754SW. Same battery, different label, so you can buy either one.

    Search Amazon for 309As an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

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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.

    SR754SW
  4. 4

    Quick facts

    Size
    About as wide as a pea
    Thickness
    As thick as 7 credit cards stacked
    Power
    1.55 volts
    Keeps in a drawer for
    About 5 years
    Rechargeable?
    No, use once
    Found in things like
    Analog watches
  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 309
    See results on Amazon →
    Amazon searchMulti-packs from any brandSearch Amazon for 309 (SR754SW) multi-packs
    See results on Amazon →
    Amazon searchDuracell listings, the same batterySearch Amazon for Duracell SR754SW
    See results on Amazon →

    Buttons open amazon.com 🇺🇸, picked from your country.

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See it at real size

SR754SW next to a US quarter and an AA battery. “Real size” matches your hand once your screen is set up in Measure it.

SR754SWThickness 5.4US quarterAA

What do the letters mean?

Battery names are a code. Here’s how to read 309:

3Watch-industry 300 series (Renata/Energizer numbering)
09Size and drain code. Maps to SR754SW, 7.9 × 5.4 mm

The same battery from each brand

BrandTheir name for it
Official nameSR754SW
Energizer309
Murata (formerly Sony)SR754SW
Renata (Swiss)309
MaxellSR754SW

Exact measurements

Width
7.9 mm (0.311 in)
Thickness
5.4 mm
Voltage
1.55V (empty at 1.2V)
Energy stored
80 mAh
Weight
—
Made with
Silver oxide
Works between
-10 … 60 °C
Official code
SR754SW

Questions people ask

Is 309 the same as SR754SW?

Yes. They’re the same battery with different names. You might also see SR754SW.

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.

SR754SW+ 1.55V
SR754SWWatch battery
Search Amazon for 309As an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

Something wrong or missing? Tell us

1What it is2Safety3Other names4Facts5Buy it