Extractor allows for easy removal of broken studs, bolts socket screws and fittings. The spiral design allows for increased grip. Set comes packaged in an organized storage case. Notes:#1 for 3/32" - 5/32", 2.5mm - 4mm, #3 to #6#2 for 5/32" - 7/32", 4mm - 6mm, #6 to #12#3 for 7/32" - 9/32", 6mm - 8mm, #12FeaturesSet contains extractors #1 through #3 and a drill bit for each extractor, sizes are 5/64", 7/64", 5/32"Left-hand spiral design, for removal of broken studs, bolts, screws and fittingsHigh carbon steel, square driveExtractor size and recommended drill bit size are etched on each extractor