Spiral flute. For removing broken screws, pipes, bolts and studs. Made of strong tool steel, heat-treated with rust-resistant chrome finish. Drill size is permanently marked on shank of extractor. No. 53401: Extractor No. 1. Screw size: 3/32 to 5/32 No. 53402: Extractor No. 2. Screw size: 5/32 to 7/32 No. 53403: Extractor No. 3. Screw size: 7/32 to 9/32 No. 53404: Extractor No. 4. Screw size: 9/32 to 3/8 and 1/8 pipe No. 53405: Extractor No. 5. Screw size: 3/8 to 5/8 and 1/4 pipe No. 53406: Extractor No. 6. Screw size: 5/8 to 7/8 and 3/8 pipe No. 53407: Extractor No. 7. Screw size: 7/8 to 1-1/8 and 1/2 pipe No. 52408: Extractor No. 8. Screw size: 1-1/8 to 1-3/8 and 3/4 pipe No. 52409: Extractor No. 9. Screw size: 1-3/8 up and 1" pipe