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Home › Can I swap? › SR621SW vs LR621
Can I swap?

SR621SW vs LR621: can you swap them?

1The short answer2Both ways3Differences4Buy it5Learn more
  1. 1

    The short answer

    YesYes, and SR621SW is the better pickSame size, and both fit. SR621SW lasts longer and gives steadier power, which matters for cameras, measuring tools and watches. LR621 is the cheaper everyday option.
    SR621SW+ 1.55V
    SR621SWAs thick as 3 credit cards stacked
    LR621+ 1.5V
    LR621As thick as 3 credit cards stacked
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  2. 2

    Both ways round

    Can I put LR621 where SR621SW goes?Yes
    Can I put SR621SW where LR621 goes?Yes
  3. 3

    What’s different

    SR621SWLR621
    SizeAbout as wide as a pencil eraserAbout as wide as a pencil eraser Same
    ThicknessAs thick as 3 credit cards stackedAs thick as 3 credit cards stacked Same
    Power1.55 volts1.5 volts
    KindWatch batteryButton battery

    Lasts longer: SR621SW (about 54% longer)

  4. 4

    Where to buy SR621SW

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

    Amazon searchEnergizer listings, any pack sizeSearch Amazon for Energizer 364
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    Amazon searchMulti-packs from any brandSearch Amazon for SR621SW multi-packs
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    Amazon searchDuracell D364 listings, the same batterySearch Amazon for Duracell D364
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  5. 5

    Learn more

    About SR621SWAbout LR621Check another pair
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Questions people ask

Can I use LR621 instead of SR621SW?

Yes. Same size, and both fit. SR621SW lasts longer and gives steadier power, which matters for cameras, measuring tools and watches. LR621 is the cheaper everyday option.

Can I use SR621SW instead of LR621?

Yes. Same size, and both fit. SR621SW lasts longer and gives steadier power, which matters for cameras, measuring tools and watches. LR621 is the cheaper everyday option.

Which one lasts longer?

SR621SW (about 54% longer).

All the numbers

SR621SWLR621
Diameter6.8 mm6.8 mm
Height2.1 mm2.1 mm
Nominal voltage1.55V1.5V
Typical capacity20 mAh13 mAh
ChemistrySilver oxideAlkaline
Shelf life5 yrs5 yrs
Operating temp-10 to 60 °C-10 to 60 °C
Can I use LR621 instead of SR621SW?Yes
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1The short answer2Both ways3Differences4Buy it5Learn more