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Home › Batteries › D364
Watch battery

D364 is the same as SR621SW

1What it is2Safety3Other names4Facts5Buy it
  1. 1

    What it is

    SR621SW+ 1.55V

    D364 is just another name for SR621SW. Same battery, different label, so you can buy either one.

    Get SR621SW 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 →
  3. 3

    Names you might see in the store

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

    SR621SW364363AG1SR60V364
  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
    Slim analog watches
  5. 5

    Where to buy it

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

    Our pickThe exact match, 4-packEnergizer D364 (SR621SW) 1.55V Battery (4-Pack)
    Check Price on Amazon →
    Best value10-pack, handy to keep in a drawerD364 (SR621SW) 1.55V Battery Value Pack (10-Pack)
    Check Price on Amazon →
    Other brandDuracell D364, the same batteryDuracell D364 / SR621SW 1.55V Battery
    Check Price on Amazon →

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

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See it at real size

SR621SW next to a US quarter and an AA battery. “Real size” matches your hand once your screen is set up in Measure it.

SR621SWThickness 2.1US quarterAA

What do the letters mean?

Battery names are a code. Here’s how to read D364:

DDuracell watch-cell prefix
3Watch-industry 300 series (Renata/Energizer numbering)
64Size and drain code. Maps to SR621SW, 6.8 × 2.1 mm

The same battery from each brand

BrandTheir name for it
Official nameSR621SW
Energizer364
DuracellD364
Renata (Swiss)364
VartaV364

Exact measurements

Width
6.8 mm (0.268 in)
Thickness
2.1 mm
Voltage
1.55V (empty at 1.2V)
Energy stored
20 mAh
Weight
—
Made with
Silver oxide
Works between
-10 … 60 °C
Official code
SR621SW

Questions people ask

Is D364 the same as SR621SW?

Yes. They’re the same battery with different names. You might also see SR621SW, 364, 363, AG1.

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.

SR621SW+ 1.55V
SR621SWWatch battery
Get SR621SW on AmazonAs an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.

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1What it is2Safety3Other names4Facts5Buy it