Designed to be used with the heavy duty fasteners referenced on the table. Receptacle is mounted with three low head cap screws (M3x0.5 - 6 mm long, included). The body is made from 1045 steel with an electroless nickel plate finish. The balls are made from 440C stainless steel. The collar is made from SKS3 steel with an electroless nickel plate finish. The retaining ring is made from 304 stainless steel.