Plug in the wall, good unit, may false trigger, but not as much as they used to. Relay closure, momemtary, sustained. Copy of X-10 UM506 test button. Great for garage doors, lawn sprinklers, window shades or other low voltage apps. You can drive AC through the relay, but it is not CSA/UL for high voltage, terminals exposed and to close. If you are ganging a few together, consider multi-relay I-O boardPricing:
1-6 7+
$C 26.08 25.69
$US 26.08 25.69
EURO 18.52 18.24
