It is always important to practice proper upkeep of your rifles to ensure they operate safely. One of the most important aspects to maintain is the bolt cleanliness. Otis understands this and has created the Otis Technology B.O.N.E. Tool to make this process as seamless and simple as possible. Make sure your rifles stay functional and safe by cleaning the bolt after every use. This B.O.N.E. Tool is made for use with .223 cal/5.56MM MSR and AR rifles. It can clean the carbon and fouling buildup from inside the bolt, bolt carrier, and the firing pin. It is durable and strong to resist wear and function properly for years to come. The tool comes equipped with an 8-32 threaded hole to accommodate T-handle functionality for even easier usage. There is occasionally some variance in rifle bolts, even among .223 cal./5.56MM MSR and AR rifles. The B.O.N.E. fits all standard bolts flawlessly, but it may fit some unusual bolts differently. Be sure to check your rifle for anomalies before purchase.