"Left handed master extractor set for removing broken bolts, studs, screws and lugs","Includes five M42 cobalt mechanic's length left-hand drill bits in 5/64\", 7/64\", 5/32\", 1/4\" and 19/64\"","For fastener thread sizes 3/32\" – 5/8\" (M3-M16)","Five matching spiral fluted screw extractors labeled to pair with corresponding drill sizes","Use with reversible drill to drill into fastener, then extractor drives itself into drilled hole to remove broken fastener without damaging threads COBALT MECHANIC'S LEFT HAND DRILL BIT EXTRACTOR KIT, 10 PIECE DEK10A | Matco Tools