Die cast metal enclosure with BEST cylinder (construction core included)
OPEN/CLOSE spring return to center (OFF) key removable in center position only. Should only be used on operators wired for constant pressure to open and close (all LiftMaster industrial operators with type D control wiring).
OPEN only (all LiftMaster operators) or SAFETY only (LiftMaster operators with type B2 C2 L2 T T1 or TS control wiring) after vehicle passes over treadle.
The weight of the vehicle compresses an electric switch which sends an open signal to the door.
Requires a 2-wire connection to the operator but does not require power to function