The Luth-AR MBA-4 Carbine Stock is designed to work with 6-position Mil-Spec buffer tubes. This stock is a direct replacement for any carbine buttstock. It features an adjustable Cheek Riser; in a low-cost, lightweight, strong, and high-quality design. The MBA-4 also features an anti-rattle set screw. The modular design of the MBA Buttstock allows you to configure your buttstock to your specific and personal needs. Built-in rail attachment for attaching a monopod.