eZ to Hook Up, No Need to Lift the Lever to Hook it Up. eZ to Latch, The Lever lifts to allow the Coupler Socket to Receive the Hitch Ball. eZ to Use, Once Seated in the Coupler, the Latch Automatically Snaps to its Locked Position. eZ Latch mechanism allows for quick engage/disengage of coupler. This coupler fits an industry standard 4-1/2 square 4-hole mounting pattern on a trailer nose plate.