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Home › Batteries › Size 312
Hearing aid battery

Size 312 battery

1What it is2Safety3Other names4Facts5Buy it6Things
  1. 1

    What it is

    312STICKER

    Size 312 is a hearing aid battery, about as wide as a pea. It gives 1.45 volts.

    Get Size 312 on AmazonAs 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 →

    Leave the sticker on until you need it

    Once the sticker is off, the battery starts running down whether you use it or not.

  3. 3

    Names you might see in the store

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

    PR41312A312ZA312V312
  4. 4

    Quick facts

    Size
    About as wide as a pea
    Thickness
    As thick as 5 credit cards stacked
    Power
    1.45 volts
    Keeps in a drawer for
    About 3 years
    Rechargeable?
    No, use once
    Found in things like
    Receiver-in-canal hearing aids
  5. 5

    Where to buy it

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

    Our pickThe exact match, 4-packEnergizer Size 312 1.45V Battery (4-Pack)
    Check Price on Amazon →
    Best value10-pack, handy to keep in a drawerSize 312 1.45V Battery Value Pack (10-Pack)
    Check Price on Amazon →
    Other brandDuracell, the same batteryDuracell Size 312 / Size 312 1.45V Battery
    Check Price on Amazon →

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

  6. 6

    Things that use Size 312

    Receiver-in-canal Hearing Aids (Size 312)Takes Size 312›
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See it at real size

Size 312 next to a US quarter and an AA battery. “Real size” matches your hand once your screen is set up in Measure it.

Size 312Thickness 3.6US quarterAA

What do the letters mean?

Battery names are a code. Here’s how to read Size 312:

312Hearing-aid size code, brown tab colour
PR41IEC zinc-air designation, 7.9 × 3.6 mm

The same battery from each brand

BrandTheir name for it
Official namePR41
Shop nameSize 312
Renata (Swiss)ZA312
VartaV312

Exact measurements

Width
7.9 mm (0.311 in)
Thickness
3.6 mm
Voltage
1.45V (empty at 1.1V)
Energy stored
180 mAh
Weight
0.5 g
Made with
Zinc-air
Works between
0 … 50 °C
Official code
PR41

Questions people ask

Is Size 312 the same as PR41?

Yes. They’re the same battery with different names. You might also see PR41, 312, A312, ZA312.

How long will a spare keep in a drawer?

About 3 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.

312STICKER
Size 312Hearing aid battery
Get Size 312 on AmazonAs an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

Something wrong or missing? Tell us

1What it is2Safety3Other names4Facts5Buy it6Things