The premium bore brushes feature a distinctive cobalt blue fiber, ensuring they stand out from traditional brushes. Designed with a thicker and stiffer grade of fiber, these brushes support effective back-and-forth cleaning action, unlike conventional brass and bronze brushes. Remarkably durable, they last approximately 8 - 10 times longer than other brushes on the market. The brush construction includes a tighter winding and a higher fiber density per inch, enhancing its cleaning efficiency. When used with the IOSSO Bore cleaner and triple action solution, these brushes effectively remove all types of fouling, including copper, lead, plastic wad, and carbon burn, significantly reducing cleaning time and delivering an exceptionally clean bore. The blue brushes are a registered trademark of IOSSO products.