ProtoA 10 Piece Bolt Extractor Socket Set Proto Bolt Extractor Sockets make it easy to remove rusted, rounded or damaged nuts and bolts The working end has a helical shaped flute to help grip rounded fasteners, round head bolts and pan head screws Proto Bolt Extractor Sockets can be used in combination with other drive tools Through-hole design helps gain access to fasteners at the end of long bolts or studs Can be used on SAE or metric fasteners