25 Socket Head Cap Screw, Chrome Plated Steel, 50 mm Length, 5 PK A hex key is required to tighten or loosen a socket screw.M8-1.. Socket screws are commonly used in assemblies that do not provide sufficient clearance for a conventional wrench or socket.
Especially useful in metal-to-metal or where heavy duty fastening is required.#6-32 x 3 in Phillips Flat Machine Screw, Zinc Plated Steel, 100 PK Commonly used with flat or lockwashers.. Machine screws are used in fastening nearly all types of hard materials.