Heavy-Duty Floor Lock 7 7/8 in For Caster Mounting Height 6 3/8 in Floor Lock Retracted Height 8 1/8 in Floor Lock Extended Height 6 in For Wheel Dia D Mounting Plate Bolt Hole Pattern 4-1/2 in x 6 in Mounting Plate Size Steel 2-1/2 in x 5 in Inside Bolt Hole Spacing 2-1/2 in x 5 in Outside Bolt Hole Spacing