Draper Stud Extractor Set, 1/2" Square Drive (4 Piece) - SESRoller type with 1 2" 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. Key Features Versatile roller type design with 1 2" square drive and 21mm hexagon socket for easy application on various fasteners. Dual functionality allows