Edwards EST SIGA-CR Control Relay ModuleThe Control Relay Module Model EST SIGA CR, is a component of the Signature Series System. The SIGA CR is an addressable device used to provide one Form "C" dry relay contact to control external appliances (door closers, fans, dampers, etc.) or equipment shutdown. The Edwards EST SIGA CR requires the Signature Loop Controller. Can be mounted in a North American 2 1 2" (64 mm) deep 1 gang box, or standard 4" square 1 1 2" (38 mm) deep box with 1 gang