Review on Enhanced Performance with Stainless Steel Shaft Collars Screw by James Pfettscher

The product corresponds to that declared. It comes complete with a 1/2" hole in the center of the ring. The set screw is turned clockwise to tighten and counterclockwise to loosen. Tightening the set screw will hold the ring in place .I would definitely buy them again if I ever need to keep the wheels on the axle.