The screw extractor set is used to remove broken screws, serrated thread and square head, different sizes to meet different needs. Features: Serrated thread elaborate design, used for the removal of broken pipe and head screw and thread screw. Square head design, more convenient to twist, can be twisted with a movable wrench. Standard caliber design of the rod, universal and convenient to use. Made from carbon steel for high hardness and durability. Include different sizes of screw extractor to meet different needs. All the tools are packed with a storage box, so convenient to carry and store. Specifications: Material: Carbon steel Color: Silver & Black Set Type: 5Pcs, 6Pcs (optional) Usable Range: #1: 4-6mm #2: 6-8mm #3: 8-11mm #4: 11-14mm #5: 14-18mm #6: 18-25mm Package Weight: 5Pcs: 102g / 3.6ounces 6Pcs: 211g / 7.44ounces Package Size: 100 * 50 * 10mm / 3.94 * 1.97 * 0.39in Packing List: 6 * Screw Extractor 1 * Storage Box