What Battery Does a Doorbell Extender Transmitter Use?
ERA and LRA extender transmitters each use one CR123A lithium battery, included, which lasts years. Plug-in receivers need no battery.
Updated: October 15, 2026Original publish date: October 15, 2026
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Both the ERA-EXTX and the LRA-EXTX transmitters run on one CR123A lithium battery, included.
- ERA-EXTX: rated for about 2 to 4 years, depending on use.
- LRA-EXTX: rated for up to about 2 years. It sends a low-battery signal to the receiver when the battery needs to be replaced.
Receivers
- ERA-RXPG and LRA-DCRXS: plug into a standard wall outlet. No battery.
- LRA-DCRX-L (in the LRA-EX1000): three C alkaline batteries, or an optional LRA-PLUG wall adapter.
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