Supply PowerMaster model "GJ" Industrial Duty Gear Reduced Jackshaft type operator rated for use on Rolling Service Doors, Rolling Grilles, and Counter Shutters. Primary speed reduction shall be by means of an industrial gear box with bronze worm gear in an oil bath. Motor shall be of the high starting torque, continuous duty industrial type, protected from overload by a current sensing or thermal type overload device. Motor controller shall be a heavy duty, full voltage, across the line, magnetic reversing contactor, that is mechanically and electrically interlocked. Electrical components shall be installed in a NEMA 1 enclosure integral to the operator. A transformer shall be provided to reduce control voltage to 24 VAC. Separate terminal strips shall be provided for connection of power supply line and all control devices. Operator shall be wired for an open/close/stop control station.