Sealey Master Extractor Set 49pc AK8149Comprehensive 49pc master extractor set, including Chrome Molybdenum screw, bolt, stud and nut extractors. Features left handed HSS drill bits, used to drill pilot holes (reversible drill is required), which often extract the fasteners bolts themselves. Spiral flute extractors for use with bolts fasteners requiring less torque. Multi spline extractors when higher torque or restricted access is required and 3 8"sq drive reverse spiral bolt extractors