Use a machine screw when you need to secure panels and parts through existing, tapped holes on everything from electronic equipment to engines to large machines. Fillister and cheese head screws have deep slots to allow increased driving power. Flat head screws lie flush with the material surface. Tamper-resistant screws are a good choice to prevent unauthorized access to electrical or control panels. Grainger has the right machine screw for your assembly or replacement job, including slotted, Phillips, tamper-resistant and hexagon head screws. Find what you need today.