Trimax Deluxe Coupler/Door Latch Lock. Ideal for trailer doors and cargo boxes. Internal O-ring in lock body and weather proof cap help seal out grime and corrosion. Protective rubber bumper prevents noisy. High security tubular key core with keys that won't bend or break. Features of Trimax TMC10 Deluxe Coupler/Door Latch Lock Easy 1/4 turn of key to lock and unlock for maximum security Ideal for trailer doors and cargo boxes Fits couplers with up to 3/4 inch span Protective rubber bumper prevents noisy rattle High security tubular key core with keys that wont bend or break Package Contents: Trimax TMC10 Deluxe Coupler/Door Latch Lock Trimax TMC10: Deluxe Coupler/Door Latch Lock