LR44 vs LR43
The LR44 and LR43 are 1.5 volt alkaline button cells, both 11.6 mm across. The LR44 is 5.4 mm tall and holds 110 to 130 mAh; the LR43 is 4.2 mm tall and holds 80 to 120 mAh. They are sold as AG13 and AG12, and they are not interchangeable.
| LR44 | LR43 | |
|---|---|---|
| Chemistry | Alkaline (Zn/MnO2) | Alkaline (Zn/MnO2) |
| Voltage | 1.5 V | 1.5 V |
| Diameter | 11.6 mm | 11.6 mm |
| Height | 5.4 mm | 4.2 mm |
| Capacity | 110-130 mAh | 80-120 mAh |
| Also sold as | AG13, A76, L1154, LR1154 | AG12, LR1142, L1142, 186 |
Assortment packs are where the mix-ups happen. The LR44 also sells as AG13, A76, L1154 and 157, and the LR43 as AG12, LR1142, L1142 and 186. Side by side in a blister card the two look almost identical, and 1.2 mm is hard to judge by eye. The code stamped on the old cell's face is the quickest way to be sure.
An LR44 will not seat in a compartment built for the LR43; the cover will not close, and pressing it shut can bend the contacts. An LR43 in an LR44 slot is the more tempting mistake, because it drops in easily. It then sits about 1.2 mm short of the contact, so the device may read dead or cut out when bumped. Where a strong spring does reach it, expect shorter runtime from the smaller cell.
Both sizes have a silver-oxide version in the identical case. The SR44, sold as 357, replaces the LR44, and the SR43, sold as 386 or 301, replaces the LR43. Silver oxide holds about 1.55 V until it is nearly spent while alkaline sags through its life, so calipers, calculators and watches read better and last longer on the silver cells. In cheap toys the alkaline cells are fine.