ULTIMAK FOR KRINKOV M13
Replaces gas tube. Clamps directly to barrel for maximum stability, accuracy, and optimum bore alignment. Solid, one-piece 6061-T6 hard anodized aluminum body. Comes with 4140 steel clamps, screws, allen wrench, and instructions. No Gunsmithing ADD AN AIMPOINT 30MM LOW RING FOR COWITNESS OR PRIMARY ARMS MIRCO RED DOT.