This relay plugs in-series with the headset or handset jack on a phone and is VOX (sound) activated.

The relay can operate a light, radio or other device when someone is using (or not using) the phone.

The DPDT relay contacts are brought out on a 6 Pin Modular Jack on the opposite side of the box (spec sheet with pinout diagram below) through a short solid wire 6 conductor cord (included) that can be punched down to a block or spliced to other wires (use UY connectors / B-Wire Connectors – not included).

Headset In-Use Relay Specs: