LanTac Nitrided Gas Tube Rifle - LanTac M-SPEC Gas Tubes. Precision manufactured from 306 stainless steel extruded tube. Lantacs M-SPEC gas tubes offer the shooter a mil-spec, high quality product at a competitive price point. * ONLY USE IF YOUR BARREL REQUIRES A RIFLE + 1 LENGTH GAS TUBE * Made in the USA ; Precision manufactured from stainless steel extruded tube; Black Nitrided for enhanced corrosion resistance, heat & erosion resistance over standard un-treated tubes; Nitrided tubes run cleaner & cooler; Black tube eliminates light reflection of the part through the handguard; Comes complete with Gas Tube Roll Pin; Laser engraved;