A23 vs A27
The A23 and A27 are both 12 volt alkaline stack batteries for remotes and small transmitters, and they are not interchangeable. The A23 is 10.3 mm across and 28.5 mm long with about 55 mAh; the A27 is a slimmer 8 mm by 28.2 mm holding roughly 22 mAh.
| A23 | A27 | |
|---|---|---|
| Chemistry | Alkaline (8-cell stack) | Alkaline (8-cell stack) |
| Voltage | 12 V | 12 V |
| Diameter | 10.3 mm | 8 mm |
| Height | 28.5 mm | 28.2 mm |
| Capacity | 50-55 mAh | 20-22 mAh |
| Also sold as | 23A, MN21, V23GA, 8LR932 | 27A, MN27, V27A, 8LR732 |
Each battery hides eight tiny alkaline cells in series inside one sleeve, which is how they reach 12 volts in a package smaller than a AAA. The A23 uses LR932 button cells, the A27 smaller LR732s, and the capacity difference follows directly: the fatter A23 stores two and a half times the energy.
Remotes are molded to one diameter. An A27 dropped into an A23 compartment rattles and loses contact; an A23 will not physically enter an A27 bay. Since both types sit side by side on store pegs, the reliable move is reading the code printed inside the remote's battery compartment or on the old cell rather than judging by memory of its size.
Garage door remotes, wireless doorbells and gate openers usually take the A23. Slim keychain car alarm remotes and pencil-thin transmitters tend to take the A27. Life expectancy in both is a year or two of clicking; radio range shrinking is the universal replacement signal, since transmit power falls with the stack's voltage.