Flexible Cylinder Hone Compatible Bore Diameter - Maximum 4 in Compatible Firearm Caliber Not Applicable Stem Diameter 0.31 in Abrasive Length 6 1/2 in Overall Length 13 1/2 in Abrasive Material Silicon Carbide Grit 320 Compatible Tool Type Combustion Cylinder Operating Speed - Maximum 600 RPM Primary Material Application Steel End Marking Color White Grade Extra Fine Stem Length 7 in