Carbon Steel Material: The damaged screw extractor set is made from carbon steel and are tempered twice for extra hardness and durability. Works on wood and machine screws, as well as flat, hex or painted over screws Remove Damaged Screws Bolts and Water Pipes: These extractors will remove most kinds of damaged, stripped, rusted, broken or stuck screws from any wood or metal surface with relative ease. The new two water pipe extractors, designed for the broken water pipes Heavy duty steel extractor, different sizes of screw extractor to meet different needs. Screw extractor size includes: 1 for 1/8\-5/32\, 2 for 5/32\-3/16\, 3 for 3/16\-1/4\, 4 for 1/4\-5/16\, 5 for 5/16\-7/16\, 6 for 7/16\-9/16\, 7 for 9/16\-3/4\, 8 for 3/4\-1\ -8-piece Widely Use: It can remove some of the common screwdriver can not be disassembled damaged bolts, screws, bolts and pipes. Reverse thread bits easily remove screws, bolts, studs and threaded pipe fittings Easy to Operate: In just easy steps, only need a drill, choose a smaller extractor than the damaged screw, can easily remove the screw, please ensure to run the drill in reverse during this process