Brownells Fillister 6-48 Sight Screw Counterbore

The Brownells Fillister 6-48 Sight Screw Counterbore is a precision gunsmithing tool designed to cut counterbores for fillister-head sight screws threaded 6-48. Used for installing front and rear sights on firearms, it ensures a clean, properly sized seating surface for screw heads. An essential tool for gunsmiths performing sight installation and replacement work on rifles, handguns, and shotguns.