NEMA 4/12 Vehicle Loop Detector, 115VVehicle Loop Detector Outdoor Enclosure (NEMA 4 12) Watertight, oil tight enclosure with single 115VAC detector, wired to terminal block for field connection. OPEN only (all LiftMaster operators) or SAFETY HOLD OPEN only (operators with type B2, T, TS or T1 control wiring) when vehicle passes over loop wire. Requires a loop of wire embedded in the ground to connect to the detector. Requires 2 wire output connection to door operator and 115VAC power.