9500-4 Agricultural Tractor Clamp Kit with Lever Actuated Quick Coupler, 1/2″ Body Size, 1/2″-14 NPTF Port End, Dust Cover on Housing. Automatic Dust Protection: The 9507-4-1H dust cover assembly with color-coded covers automatically closes when couplers are disconnected, preventing dirt from entering the coupler socket and ensuring clean operation.