Pro-Shot Patriot Nylon Brush - Stiff bristles remove fouling but will not damage bore. Heavy duty bore brush is great for heavily fouled barrels. Stiff heavy duty red, white, and blue nylon bristles. Will not flatten like standard brass bristles brushes. Manufactured with solid Brass Core & Coupling. Stiff Colored bristles resist ammonia and oil-based cleaners. Standard American #8-32 Thread Made in USA