This is a Yankee Hill Machine Co Handguard known as the 7.3" Diamond Series Forearm (C, model YHM-9630-DX.
These unique forearms feature diamond shaped heat vents" an extended top rail for gap-free installation" "T" marked rails to mark accessory locations" they accept their end caps" and utilize their anti-rotation screws for secure installation. The forearms and barrel nuts are made of 6061-T6 aluminum and hardcoated to military specifications. The jam nut and anti-rotation screws are steel and plated a matte black finish to match.
Features:
Black finish
7.3 Black Diamond carbine length forearm;Comes with all necessary parts for installation;Fits AR-15