Flexible Cylinder Hone Compatible Bore Diameter - Maximum 1 1/8 in Compatible Firearm Caliber Not Applicable Stem Diameter 0.21 in Abrasive Length 3 in Overall Length 7 7/8 in Abrasive Material Silicon Carbide Grit 320 Compatible Tool Type Combustion Cylinder Operating Speed - Maximum 800 RPM Primary Material Application Steel End Marking Color White Grade Extra Fine Stem Length 4 7/8 in