Flexible Cylinder Hone, Compatible Bore Diameter – Maximum 3 in, Compatible Firearm Caliber Not Applicable, Stem Diameter 0.25 in, Abrasive Length 3 in, Overall Length 8 in, Abrasive Material Aluminum Oxide, Grit 40, Compatible Tool Type Brake Cylinder, Wheel Cylinder, Operating Speed – Maximum 900 RPM, Primary Material Application Stainless Steel, Compatible Bore Diameter – Minimum 3 in, End Marking Color Purple, Stem Marking Color Black