Yankee Hill Carbine Length Diamond Series Forearm is a unique forearm that features diamond shaped heat vents. Has extended top rail for gap-free installation, "T" marked rails to mark accessory locations and they accept Yankee Hill end caps and utilize anti-rotation screws for secure installation. The forearms and barrel nuts are made of 6061-T6 aluminum and hardcoated to military specifications. Now that's STRONG! The jam nut and anti-rotation screws are steel and plated a matte black finish to match. Assemblies include: one jam nut, one barrel nut, two anti-rotation screws, and one forearm tube. Overall Length 7.2 Inches. Weight 12.5 oz.