front sight base FSB .625 w/o bayonet lug
offered for sale is a black mil spec F-marked, FSB without bayonet lug for lightweight barrel with .625 diameter.
this is a basic forged front sight base which requires gunsmith installation by drilling and tapping permanent pins. This is a phosphated F-marked front sight base, stripped. Looks like Colt, not sure on origin, but identical to Colt, for narrow barrels with 0.625” gas block profile.