A while back, I had purchased a MCTAR-20P handguard for a piston conversion. I had forgotten the exact sequence of installation and when I attempted to take it apart, I messed up and had forcefully disassembled the barrel nut inserts on the top half, and messed up the threads on the inserts. Way dumb on my part, but as I get older, I tend to forget a lot of stuff. As an aside, the piston handguards were perfect fits for my conversions. No milling was necessary, as with some other products. I contacted Troy and e-mailed him about my dilemma and asked if he could sell me a pair of the inserts. He replied that he would look around to see if there were any spares laying around. Well, two weeks later, I unexpectedly receive an complete new unit to replace the unit that I had screwed up. Totally outstanding customer service! I had ordered several items in the past from MI, and their product quality and innovation is superb. Now you can add in excellent and outstanding customer service. To go out of their way to take care of their customers is not a quality you find in many companies, but MI is tops where it counts. They have my business for life. Thanks, Troy.