Socket head cap screws are commonly used in machine assembly, especially for removable panels and parts. They have a round cap with a hex head and are tightened with a socket wrench drive. Choose the right cap head for your specific application. Longer caps are easier to see when fastened, while button and flat head caps are less apt to snag clothing or linkages. Chrome cap screws have a great appearance. Those with a black oxide or armor coat finish resist corrosion. Stock up on socket head cap screws from Grainger to expedite engine and machine maintenance.