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. May be used in thin metal (less than .050 thick). Eliminates need for pre-drilled or pre-punched holes. The head design offers low clearance and an extra large bearing surface. AISI 1018 - 1022 or equivalent steel. Screws shall be quenched in liquid and then tempered by reheating.