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| Size 312 | LR721 | |
|---|---|---|
| Size | About as wide as a pea | About as wide as a pea Same |
| Thickness | As thick as 5 credit cards stacked | As thick as 3 credit cards stacked |
| Power | 1.45 volts | 1.5 volts |
| Kind | Hearing aid battery | Button battery |
Lasts longer: Size 312 (about 900% longer)
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No. They’re the same size, but hearing aid batteries breathe air through tiny holes to work. Don’t mix them with ordinary button batteries.
No. They’re the same size, but hearing aid batteries breathe air through tiny holes to work. Don’t mix them with ordinary button batteries.
Size 312 (about 900% longer).
| Size 312 | LR721 | |
|---|---|---|
| Diameter | 7.9 mm | 7.9 mm |
| Height | 3.6 mm | 2.1 mm |
| Nominal voltage | 1.45V | 1.5V |
| Typical capacity | 180 mAh | 18 mAh |
| Chemistry | Zinc-air | Alkaline |
| Shelf life | 3 yrs | 5 yrs |
| Operating temp | 0 to 50 °C | -10 to 60 °C |