The Luth-AR A2 Buttstock Kit is a fixed rifle-length stock setup for the AR-15. It uses the classic A2 fixed stock in black with a trapdoor storage compartment, mounted on a rifle-length receiver extension. This is the traditional full-length configuration for rifle-length builds and service-style rifles. Features: Luth-AR fixed A2 buttstock in black Trapdoor storage compartment in the stock Rifle-length receiver extension (buffer tube) Stock screw and spacer included Classic A2 fixed-stock profile This is a rifle-length system only. It is not interchangeable with carbine collapsible stock hardware. Component lists can vary by SKU, so verify the full bill of materials for your build needs before ordering.