<p>A screw having undergone trivalent chromium chemical coating treatment that exhibits approximately the same torque characteristics as those of hexavalent-chromate-treated screws. For obtaining the screw, a bolt surface is furnished with a zinc plating layer through zinc plating treatment, and the zinc plating layer on its surface is further furnished with a trivalent chromium chemical coating through trivalent chromium chemical coating treatment. This coating is provided thin and soft so that by bolt tightening, the trivalent chromium chemical coating at a point of contact of the bolt with a tightened member is shaved to thereby realize surface exposure of the zinc plating layer.</p>
