A bolt face that is truly perpendicular to the bore will result in enhanced accuracy in bolt action rifles. This tool by PTG squares the bolt face to the rifle bore, reducing case stress and enhancing accuracy and reliability. Cutter guides are useful for properly aligning a cutter with a bolt face. Notes: .550" actual cutting diameter.375" diameter drive shankRequires use of PTG Bolt Face Truing GuidesCutter is multi fluted for a smooth cut