The tapered bronze bristles of the Otis chamber brush scrub the chamber, neck and shoulder. The steel bristles at the base scrub the star chamber of the locking lugs. The brass stem is cold welded to the core, and the tip is folded, not cut. The chamber brush has a standard 8-32 thread.
It is available in either 5.56MM (essential for anyone that shoots an M4/M16/AR15) or (this version) 7.62MM (essential for anyone that shoots a 7.62MM rifle).