Daniel Defense was awarded the Naval Surface Warfare Center - Crane Division contract for the MK12 low profile gas block. As a result we are able to offer this gas block commercially. This gas block is built to Crane specification for USSOCOM. Details * Hardened 416 Stainless Steel * Black Oxide Coated * Precision CNC Machined * Weights 1.9 oz * Made in USA Includes * Low profile gas block * (2) set screws * Gas tube roll pin * 0.5 ml. LOCTITE 262 Threadlocker The Gas Block of USSOCOM!