XTS MICRO-GB MICRO GAS BLOCK FOR AR-15 by Xtreme Tactical Sports $6.95 1 2 3 4 5 6 7 8 9 10+ Quantity Quantity Add to cart Low Profile Micro Gas Block - AR-15 Aluminum Construction .750 Diameter Fits AR-15 .223/5.56 NATO Barrel Dual set screws Includes gas tube roll pin Matte black finish Best used with free float systems