Yankee Hill Carbine Length Lightweight Four Rail Forearm utilize anti-rotation screws to insure the forearm stays solid even under strenuous use. This forearm is perfect for use with forward grips and optics. Features mounting points for Swiveling Sling Studs, Mil. Spec. Picatinny rails, and they accept Forearm End Caps. The barrel nut and forearm tube are made of aircraft quality aluminum and hardcoat anodized to Mil. Specs. The jam nut is made from steel and plated a matte black to match. All assemblies include one jam nut, one barrel nut, 2 anti-rotation screws, and one forearm tube. Overall length of thre Carbine Length Lightweight Four Rail Forearm is 7.2 inches and weight is 10.6 ounces.