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Home › Can I swap? › Size 312 vs SR731SW
Can I swap?

Size 312 vs SR731SW: can you swap them?

1The short answer2Both ways3Differences4Buy it5Learn more
  1. 1

    The short answer

    NoNo, hearing aid batteries are differentThey’re the same size, but hearing aid batteries breathe air through tiny holes to work. Don’t mix them with ordinary button batteries.
    312STICKER
    Size 312As thick as 5 credit cards stacked
    SR731SW+ 1.55V
    SR731SWAs thick as 4 credit cards stacked
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  2. 2

    Both ways round

    Can I put SR731SW where Size 312 goes?No
    Can I put Size 312 where SR731SW goes?No
  3. 3

    What’s different

    Size 312SR731SW
    SizeAbout as wide as a peaAbout as wide as a pea Same
    ThicknessAs thick as 5 credit cards stackedAs thick as 4 credit cards stacked
    Power1.45 volts1.55 volts
    KindHearing aid batteryWatch battery

    Lasts longer: Size 312 (about 386% longer)

  4. 4

    Where to buy Size 312

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

    Amazon searchEnergizer listings, any pack sizeSearch Amazon for Energizer Size 312
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    Amazon searchMulti-packs from any brandSearch Amazon for Size 312 multi-packs
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    Amazon searchDuracell listings, the same batterySearch Amazon for Duracell Size 312
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    Buttons open amazon.com 🇺🇸, picked from your country.

    Search Amazon for SR731SWAs an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.
  5. 5

    Learn more

    About Size 312About SR731SWCheck another pair
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Questions people ask

Can I use SR731SW instead of Size 312?

No. They’re the same size, but hearing aid batteries breathe air through tiny holes to work. Don’t mix them with ordinary button batteries.

Can I use Size 312 instead of SR731SW?

No. They’re the same size, but hearing aid batteries breathe air through tiny holes to work. Don’t mix them with ordinary button batteries.

Which one lasts longer?

Size 312 (about 386% longer).

All the numbers

Size 312SR731SW
Diameter7.9 mm7.9 mm
Height3.6 mm3.1 mm
Nominal voltage1.45V1.55V
Typical capacity180 mAh37 mAh
ChemistryZinc-airSilver oxide
Shelf life3 yrs5 yrs
Operating temp0 to 50 °C-10 to 60 °C
Can I use SR731SW instead of Size 312?No
Search Amazon for Size 312As an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

Something wrong or missing? Tell us

1The short answer2Both ways3Differences4Buy it5Learn more