TDC® Greenfield® Chicago-Latrobe® Screw Extractor, Size: #7, List Number: 800, 1/2" Small End Diameter, Large End Diameter: 0.7812", 4-1/8" Overall Length, 2-1/4" Flute Length, Screw/Stud Size: 1 to 1-3/8", Drill Size: 17/32", Material: Alloy Steel, Finish: Bright, Applicable Materials: Alloy Steel, Tool Steel, Low and Medium Carbon Steel, Cast Iron