Iosso's Eliminator brushes offer thicker bristles than normal nylon brushes for better scrubbing action. This makes the tedious chore of bore cleaning quicker and easier. These nylon brushes won't harm your bore and are impervious to ammonia-based solvents and cleaners. Perfect for handgun, rifle, shotgun and blackpowder applications. Brass wire core is looped at the end of the brush, rather than being cut off, to protect firearm chamber and throat from scratches. These nylon brushes are designed for use with harsh solvents or polished bores.