I dont think all AR parts are strictly U.S. only.Some mfgs contract foreign companies to build their parts to excact tolerances,they inspect them there and then in the U.S. when they arrive and distribute them out.When they do this the U.S. companies look at the cheaper labor market and use it to their advantage and pass the savings to the buyer.Do some mfgs make better quality parts than others?Sure they do,thats when WE find out how good they are(if they break or how long they last)over other mfgs.I dont see how you can tell U.S. from foreign,nor do i care at this point,because the markets so flooded.With that said is COLT all U.S. made?Company reps will say they are as a selling point.Some LPK kits fit tight and some drop in with no problem,which are which?IMO if the parts work and are decent priced,then ill buy them.If youre that concerned then make them prove the parts are all U.S. made.