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). Body made from 303 stainless steel with an electroless nickel plate finish. Balls made from 440C stainless steel. The collar made from quenched and tempered 440C stainless steel. Retaining ring made from 304 stainless steel.