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Home › Can I swap? › LR1120 vs MR42
Can I swap?

LR1120 vs MR42: can you swap them?

1The short answer2Both ways3Differences4Buy it5Learn more
  1. 1

    The short answer

    NoLR1120 can stand in for MR42, but not the other way roundThey’re the same width and power, but LR1120 is thinner. It may wobble a little and runs out about 49% sooner. MR42 is too thick to fit where LR1120 goes.
    LR1120+ 1.5V
    LR1120As thick as 3 credit cards stacked
    MR42+ 1.4V
    MR42As thick as 5 credit cards stacked
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  2. 2

    Both ways round

    Can I put MR42 where LR1120 goes?No
    Can I put LR1120 where MR42 goes?In a pinch
  3. 3

    What’s different

    LR1120MR42
    SizeAbout as wide as a shirt buttonAbout as wide as a shirt button Same
    ThicknessAs thick as 3 credit cards stackedAs thick as 5 credit cards stacked
    Power1.5 volts1.4 volts
    KindButton batteryButton battery

    Lasts longer: MR42 (about 95% longer)

  4. 4

    Where to buy LR1120

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

    Amazon searchEnergizer listings, any pack sizeSearch Amazon for Energizer 191
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    Amazon searchMulti-packs from any brandSearch Amazon for LR1120 multi-packs
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    Amazon searchDuracell D191A listings, the same batterySearch Amazon for Duracell D191A
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    Buttons open amazon.com 🇺🇸, picked from your country.

    Search Amazon for MR42As an Amazon Associate, KnowYourBatteries.com earns from qualifying purchases.
  5. 5

    Learn more

    About LR1120About MR42Check another pair
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Questions people ask

Can I use MR42 instead of LR1120?

No. They’re the same width and power, but LR1120 is thinner. It may wobble a little and runs out about 49% sooner. MR42 is too thick to fit where LR1120 goes.

Can I use LR1120 instead of MR42?

In a pinch. They’re the same width and power, but LR1120 is thinner. It may wobble a little and runs out about 49% sooner. MR42 is too thick to fit where LR1120 goes.

Which one lasts longer?

MR42 (about 95% longer).

All the numbers

LR1120MR42
Diameter11.6 mm11.6 mm
Height2.1 mm3.6 mm
Nominal voltage1.5V1.4V
Typical capacity41 mAh80 mAh
ChemistryAlkalineMercury oxide
Shelf life5 yrs5 yrs
Operating temp-10 to 60 °C-10 to 60 °C
Can I use MR42 instead of LR1120?No
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1The short answer2Both ways3Differences4Buy it5Learn more