SOLGW NTC BCG is the direct result of nearly 2 years' worth of research and testing on advanced coatings; optimized for extended service life, high lubricity, and best-in-class corrosion resistance. While their standard phosphate-treated bolt carriers are fantastic and hold lubrication in place, the NTC coating they've selected is extremely slick even without lubrication. The low-friction coating does a phenomenal job of shedding carbon as well, making even suppressed use cleanup a breeze.