DKS 9235 Max Security Slide Gate The Doorking 9235 Series operators are designed to operate vehicular sliding gates weighing up to 3000 Lbs. These operators have a variable speed drive with slow-start / slow-stop circuitry. The mounting pedestal is included. A chain support tray is recommended for gates exceeding 20 feet in length. These operators offer speeds of up to 4 ft./sec and have a special Emergency Close feature that will close the gate at 6 ft./sec. These operators include a mechanical disc braking system.