TDC® Greenfield® Chicago-Latrobe® Screw Extractor, Size: #3, List Number: 800, 1/8" Small End Diameter, Large End Diameter: 1/4", 2-3/4" Overall Length, 1" Flute Length, Screw/Stud Size: 5/16 to 7/16", Drill Size: 5/32", Material: Alloy Steel, Finish: Bright, Applicable Materials: Alloy Steel, Tool Steel, Low and Medium Carbon Steel, Cast Iron