This tire swivel has 3 prongs to help prevent chains from tangling. Our extra heavy-duty commercial tire swivel has a top plate for added strength and a rubber boot to prevent fingers from being pinched. The top plate has four holes for attaching to a wood beam. The plate is 5 ½ ” long and 5 1/2” wide with four 3/8” holes that are 3 ½ ” center to center.  There is a welded nut securing the swivel to the plate. The entire swivel is 9” long.  It hangs down 8 1/2″ from the pipe. Holes are round not oblong. Powder coated in a bright red finish.