Helps keep the weight down when adding heavy tactical optics to your M14/M1A. Three-point design clamps down solidly, without alteration, to the side receiver ring, charger guide dovetail and receiver mount lug. Precision-cut rail includes 5º angle milled on the underside for easy case ejection without hang-ups; accepts Picatinny and Weaver-style rings. Open sight channel gives unobstructed view of back-up iron sights. Standard model is available in three strength-to-weight combinations. Steel model is fully machined from stress-relieved 4142 chrome-moly steel barstock, hardened to Rc 28-32 for maximum strength. Aluminum model is machined from 7075 bar stock aluminum and hardcoat anodized matte black for durability. Airborne model features a lightweight skeletonized frame with seven, 3/8" diameter CNC machined lightening holes in the top of the rail for reduced weight without sacrificing strength. Machined from chrome-moly steel bar stock and heat-treated to Rc 50 for superior strength. Mil-Spec Parkerized finish resists abrasion and corrosion. Adopted by the 101st Airborne.