Shoulder: Shoulder refers to the enlarged portion of the screw, the diameter of which serves as the basis for derivation of nominal size. Length: The length of the shoulder screw shall be measured, parallel to the axis of the screw, from the plane of the bearing surface under the head to the plane of the shoulder at the threaded end. Manufactured to: ASME B18.3, ASTM F837 Specifications and Standards Shoulder Diameter: 5/16 x Shoulder Length: 1/2 Thread Size: 1/4-20 Nominal Hexagon Socket (allen wrench) size: 5/32 (Inch) Brand Newport Fasteners Color Silver Head Type Socket Size Name 1/4-20 x 1/2 inch Metal Type Stainless Steel Part Number 665619 Thread Size 1/4-20 Thread Type Unc Drive System Internal Hex Manufacturer Newport Fasteners Thread Style Right Hand Fastener Type Machine Screw Material Type stainless_steel_18-8 Exterior Finish Stainless Steel Thread Coverage Fully Threaded Screw Head Style Socket Set Screw Thread Type Coarse