These premium bore brushes are made with a fiber that is cobalt blue in color so it can't be mistaken for any other type brush. This thicker, stiffer grade of fiber allows for back and forth action unlike traditional brass and bronze type brushes. They last approximately 8 to 10 times longer than other brushes. The brush is wound tighter and has more fiber per inch than any other brush. Use with the Iosso Bore Cleaner and Triple Action Solution to remove all ; copper, lead, plastic wad, and carbon burn. It drastically reduces cleaning time and the result is an unbelievably clean bore. These brushes are available in rifle, pistol, shotgun and black powder sizes. The blue brushes are a Trademark of Iosso Products.