Center the extractor tip into the screw head and rotate counterclockwise to loosen. For broken screw shafts or screws, than you will need to drill a starting hole in the middle before you use the extractor so that the extractor has something to grip. Features:Made of chrome vanadium steel hardened for longer life and durability Anti-clockwise design Comes with a reusable plastic storage case. Designed to remove stubborn, rusty, stripped, bolts or bolts, even factory-installed carriage type screws with no gaps to remove. Material: Chrome Vanadium Stainless Steel Color: As the picture shownEach bit is for sizes 1/8-1/4" (3-6mm), 1/4-5/16"(6-8mm), 5/16-7/16" (8-11mm), 7/16-9/16"(11-14mm) or 9/16-3/4" (14-18mm)5 x Screwdriver