Unbranded #10-24 x 9/16 in. Brass Expansion Nut

This expansion nut, or well nut, is comprised of 2 parts: a rubber outer sleeve with a flange that serves as a plug, and a brass insert. The plug is placed into the hole and a bolt is inserted. Upon tightening the bolt, the end of the rubber backs up toward the flange, expands, and anchors itself within the hole. They are good for applications where light sealing and vibration dampening are needed.