Split Panel Brackets, accommodate any size roller to your trailer so you can vertically adjust the roller to stabilize your boat, and not have to worry about what size roller you&';ve got! Sold in pairs (right and left) to accommodate any size roller length Slot allows vertical adjustment for stabilizing boat on trailer Slots accept 7/16" or 1/2" bolts Use 1/2" or 5/8" roller shaft Slot Length: 5" 2 Pack