Brownells 10mm/.40 Cal #8-32 Male Double-Tuff Bore Brush, Pack of 3

The brass coupling and the one-piece, looped and wound brass shank, equipped with extra-thick, kinked phosphor bronze bristles, provide the robust scrubbing action necessary to effectively remove stubborn debris and fouling. Although significant effort is required, the results are highly satisfactory. Phosphor bronze bristles, known for their superior conductivity and corrosion resistance, are engineered to optimize performance in demanding electrical and mechanical applications Brass, looped and wound shank Compatible with 8-32 internal threaded components