Flexible Cylinder Hone, Compatible Bore Diameter – Maximum 3 3/4 in, Compatible Firearm Caliber Not Applicable, Stem Diameter 0.31 in, Abrasive Length 3 1/2 in, Overall Length 13 1/2 in, Abrasive Material Silicon Carbide, Grit 320, Compatible Tool Type CNC Machine, Drill, Drill Press, Operating Speed – Maximum 900 RPM, Primary Material Application Cast Iron, Steel, Stainless Steel, End Marking Color Not Applicable, Grade Extra Fine, Stem Marking Color Not Applicable