The San Tan Tactical AR-15, LR-308 Gas Tube is a nitride coated gas tube that is an essential component for the AR-15 family of firearms. Precision machined from 304 Stainless Steel, STT AR15/AR10 gas tubes have an extremely durable Nitride finish that increases corrosion resistance, wear resistance, fatigue strength and cosmetic appeal while ensuring consistent gas flow to help your rifle cycle properly. This gas tube includes the gas tube roll pin.