Otis 3 piece combo set is comprised of 5 scrapers and two all purpose brushes. These detailed scrapers cover a magnitude of cleaning - firing pins, bolts, chamber, slides, trigger group and more. Scrub hard to reach areas with the stiff nylon bristles or scrape fouling build up with the various scrapers. 2 all purpose brushes are composed of a stiff blue nylon to scrub carbon and fouling accumulated from hard to reach areas, 5 scrapers to remove caked on carbon and fouling- angled scraper, flat scraper, pick, bolt scraper and firing pin scraper.