Sealey ak751 bolt stud and screw extractor set 18 piece sealey ak751 p this 18 piece bolt stud and screw extractor set from sealey is a comprehensive set including chrome molybdenum screw and bolt extractors and vanadium stud extractors screw type has left hand threads for removing recessed bolts studs bolt type features reverse spiral flutes which bite down on rounded off bolts stud type includes 3 internal rollers clamping down and gripping stud allowing removal installation p p