Flexible Cylinder Hone, Compatible Bore Diameter – Maximum 4 1/2 mm, Compatible Firearm Caliber Not Applicable, Stem Diameter 0.06 in, Abrasive Length 3/4 in, Overall Length 6 in, Abrasive Material Aluminum Oxide, Grit 800, Compatible Tool Type Brake Cylinder, Wheel Cylinder, Operating Speed – Maximum 1,200 RPM, Primary Material Application Stainless Steel, Compatible Bore Diameter – Minimum 4 1/2 mm, End Marking Color Blue, Stem Marking Color Black