The Hillman Group 7659 Round Head Combo Machine Screw with Nut, 6-32-Inch x 1 1/2-Inch, 8-Pack Machine screws are used with nuts or screwed directly into a threaded receptacle to fasten metal parts together If nuts are needed, use with nuts of the same finish and threading for proper fit Fasten with a screwdriver to reduce the risk of over-tightening to protect the screw and fastened material