Compact bodies leave more room for wires in the box, but that isn t the only way these durable Pass Seymour® Hospital Grade Receptacles speed installation. They also feature an auto-ground and screw-pressure-plate back wiring (with the option of side wiring). Long service life is ensured by one piece, triple-wipe brass power contacts and a heavy-gauge strap that is locked into the high strength thermoplastic back body. A sturdy mechanical shutter system helps prevent children from inserting objects into the receptacle.