The Iosso Eliminator Rifle Brush for .30/.308 caliber firearms features premium cobalt blue fiber construction that allows for superior back-and-forth cleaning action unlike traditional brass and bronze brushes.Iosso Eliminator Rifle Brush for .30/.308 caliberProprietary cobalt blue fiber - thicker and stiffer than standard brushesWound tighter with more fiber per inch for superior cleaningReusable design - can be used several times before wearing outCompatible with Iosso Bore Cleaner and Triple Action SolutionRemoves copper lead plastic wad and carbon foulingDesigned to drastically reduce cleaning time while achieving an exceptionally clean bore. The distinctive blue fiber is a trademark of Iosso Products ensuring you're getting authentic premium cleaning performance for your rifle maintenance needs.