WHAT DOES BCM COMPLETE LOWER MEAN?

I’ve purchased two of these blems and they are excellent worth when caught on sale. One was flawless together with other had scratched anodizing on set off guard ears (high-quality by me as my equipment get utilised and abused). Equipped having an Improved set off guard, BCM PNT (Polished Nickel Teflon) trigger, and Mod 3 pistol grip, this assem