Pro Shot 6mm/.243 Rifle Brush - Pro-Shot Premium Heavy Duty Nylon Bristle bore brushes are made with a tightly wound brass core and oversized extra thick fill bristles. The thicker, stiffer grade bristles allow for back and forth action and eliminate heavy fouling fast. Features: Pro-Shot Bore Brush - Precision Engineered Design, Fit, & Function Superior Heavy Duty Stiff Nylon Bristles with Extra Thick Fill Precision #8-32 Threads Made in USA