This came from a Colt model 6601 with only 200 rounds at most thru it. It is preban with flash suppressor, no bayo lug, A2 sights, 20" barrel, 1x7 Twist Rate, charging handle, bolt and bolt carrier. All 100% Colt. I converted the rifle into a M4 config. Price is $425 plus shipping. For additional $25 I will include a front site assembly with bayonet lug for the HBAR. Satisfaction quaranteed.