Screw: 5/16-18 Set Screw Shaft Collars are the most cost effective shaft collar design. They are available in zinc plated, black oxide, stainless steel, aluminum and bare steel. Lightweight styles are available where an application has a space constraint. If additional load capacity is required, Set Screw Collars are possible with a second screw at 90°. Set Screw Collars can be ordered as a special with a keyway for keyed shafts.