The PowerMaster SL sliding door operator from North Shore Commercial Door is designed for commercial applications. PowerMaster's SL door operator has a high-starting torque motor with full overload protection. This mechanically self-locking slide door operator has a heavy-duty V-belt and chain reduction, adjustable torque limiting clutch and disconnect arm for manual operations during power outages. Choose yours with 1/2hp to 1hp horsepower and voltage from 115/230 1ph or 208/230/460 3ph. A 3-button control station and heavy-duty #41 roller chain is included with positive chain-driven rotary limit switches. PowerMaster's American-made SL has a durable baked-on gray powder coat finish.