45681-513 Apollo Detector Base with Integral Sounder 17-60VDC, 16mA, 95dBA + Diode

The Series 65 Sounder Base is a high-efficiency conventional alarm sounder
incorporating a base for the Series 65 range of detectors.
It is designed so that separate detector and sounder circuits can be connected.
The sounder base can be secured to a conduit box or surface mounted.