1、This set is designed to remove damaged, rusted or stripped screws, bolts, fasteners. 2、Various sizes for screws of diameter 4mm -18mm/4mm-25mm. 3、Easy to use, drill a hole in the center of broken screw first, then use a proper extractor to take screw out. 4、You may use an adjustable wrench to hold extractor firmly when removing screw. 5、Suitable to maintain household, office, and so on. Features: 1. This set is designed to remove damaged, rusted or stripped screws, bolts, fasteners. 2. Various sizes for screws of diameter 4mm -18mm/4mm-25mm. 3. Easy to use, drill a hole in the center of broken screw first, then use a proper extractor to take screw out. 4. You may use an adjustable wrench to hold extractor firmly when removing screw. 5. Suitable to maintain household, office, and so on. Specification: Material: Chrome-vanadium Steel Color: As Pictures Shown Options: 5pcs, 6pcs Weight: Approx. 121-226g Suitable Screws(Diameter): 1#: 4~6mm 2#: 6~8mm 3#: 8~11mm 4#: 11~14mm 5#: 14~18mm 6#: 18-25mm Package List: 1 * 5pcs/6pcs screw extractor