NBS Gas Tubes are high quality and affordable parts helping your AR-15 or LR-308 function reliably. Made of durable stainless steel, these gas tube are built to strict mil-spec standards and come in a variety of length classes. Make sure your rifle functions flawlessly with an NBS Gas Tube. Gas tube roll pin is included.Features: High Quality Affordable Nitride Coated Built to Mil-Spec Standards