Diameter: #10 Length: 1-1/4 Material: Steel Finish: Plain Head Style: Flat (1/8 Socket) Thread Size: 32 (Fine) Thread Length: Partial Type: Socket Cap Screw Box of 100. A socket cap screw is a type of cap screw with a hexagonal recessed drive. A hex key is required to tighten or loosen a socket screw. Socket screws are commonly used in assemblies that do not provide sufficient clearance for a conventional wrench or socket.