Change the look of your G3 by swapping your factory Stainless Steel barrel for a different look. DLC stands for diamond like carbon. It is a PVD (physical vapor deposition) coating that greatly improves the durability and corrosion protection of the barrel. Furthermore, it has very good lubricity and improves your firearm performance. PVD (physical vapor deposition) coatings are extremely hard with a low coefficient of friction resulting in significant improvements in durability and performance.