PICTURES ARE REPRESENTATIVE OF ITEM, BUT ARE NOT OF THE ACTUAL ITEM. Product dimensions, finish, head markings, thread length, stamping shape or forging shape, etc., may differ from picture. Products are guaranteed to meet the specifications to which they are manufactured. Specifications allow for tolerances in dimension and shape, which can vary from lot to lot. For use in applications where the fastener is frequently adjusted and where tightening torque greater than that achieved with finger pressure is not required. A shoulder-pattern allows the head of the screw to seat flush against the mating surface and helps avoid over-tightening of the fastener which could result in stripped mating threads. Steel: Commercial quality carbon steel. Stainless: 18-8 Stainless.