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Home › Batteries › SR66
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SR66 is the same as SR626SW

1What it is2Safety3Other names4Facts5Buy it6Swaps
  1. 1

    What it is

    SR626SW+ 1.55V

    SR66 is just another name for SR626SW. Same battery, different label, so you can buy either one.

    Get SR626SW on AmazonAs an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

    Something wrong or missing? Tell us

  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.

    SR626SW377376AG4D377V377
  4. 4

    Quick facts

    Size
    About as wide as a pencil eraser
    Thickness
    As thick as 3 credit cards stacked
    Power
    1.55 volts
    Keeps in a drawer for
    About 5 years
    Rechargeable?
    No, use once
    Found in things like
    Analog wristwatches (Swatch, Seiko, Timex)
  5. 5

    Where to buy it

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

    Our pickThe exact match, 4-packEnergizer SR66 (SR626SW) 1.55V Battery (4-Pack)
    Check Price on Amazon →
    Best value10-pack, handy to keep in a drawerSR66 (SR626SW) 1.55V Battery Value Pack (10-Pack)
    Check Price on Amazon →
    Other brandDuracell D377, the same batteryDuracell D377 / SR626SW 1.55V Battery
    Check Price on Amazon →

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

  6. 6

    Can I use something else?

    Can I use 377 instead of SR626SW?Yes
Show more details (optional)

See it at real size

SR626SW next to a US quarter and an AA battery. “Real size” matches your hand once your screen is set up in Measure it.

SR626SWThickness 2.6US quarterAA

What do the letters mean?

Battery names are a code. Here’s how to read SR66:

SSilver oxide chemistry (1.55V)
RRound button form factor
66Legacy IEC size number, not a dimension. Actual size 6.8 × 2.6 mm

The same battery from each brand

BrandTheir name for it
Official nameSR626SW
Energizer377
DuracellD377
Murata (formerly Sony)SR626SW
Renata (Swiss)377
VartaV377
MaxellSR626SW

Exact measurements

Width
6.8 mm (0.268 in)
Thickness
2.6 mm
Voltage
1.55V (empty at 1.2V)
Energy stored
28 mAh
Weight
0.4 g
Made with
Silver oxide
Works between
-10 … 60 °C
Official code
SR626SW

Questions people ask

Is SR66 the same as SR626SW?

Yes. They’re the same battery with different names. You might also see SR626SW, 377, 376, AG4.

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.

SR626SW+ 1.55V
SR626SWWatch battery
Get SR626SW on AmazonAs an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

Something wrong or missing? Tell us

1What it is2Safety3Other names4Facts5Buy it6Swaps