It is compact, rugged, and inexpensive, and has a DeviceNet eurofast connector. The unit fits into any standard pushbutton enclosure. To mount, drill a hole in the center of the bottom of the pushbutton enclosure. Insert the eurofast connector into the hole and tighten the lock nut. The connector extends out the base of the pushbutton enclosure and connects to a network drop cable. I/O screw terminals are easily accessible inside the enclosure. No other cables are needed. The FDN20 powers its input and outputs from DeviceNet.