This is Colt lower from a Colt factory rifle. All parts are original Colt as assembled by Colt at the Colt factory, excepting the Magpul MIAD bolt-pin grip. Sear block is removed so a full auto bolt can be used. The lower is 100% reliable and with a quesstimate less than 1500 rounds fired. Price is $1400 plus actual shipping cost, approximately $35 Payment via a certified bank check or Postal Money order. My gunbroker account is SJC3081 for feedback confirmation. PM for questions.