Draper 12 square drive 4 piece stud extractor set draper 58709 the draper stud extractor 8mm is a roller type with 12 square drive or 21mm hexagon on end of socket unscrews both left and right hand threads manufactured from chrome vanadium steel hardened tempered and chrome plated for corrosion protection spare extractors are available separately packed in metal case in display sleeve draper 58709 stud extractor 8mm