Luth-AR MBA-1 Buttstock is a fully adjustable, ambidextrous modular buttstock assembly for AR-style rifles chambered in .308/7.62mm. Constructed from super-strong glass-filled nylon in black. Kit includes .308/7.62 buttstock extension tube, standard .308/7.62 buffer spring, and standard buffer body assembly (5.3 oz). Features adjustable cheek rest (+1 height) and extended length of pull (+1 1/16). LOP 10.50-11.50, weight 18.40 oz. Sling swivels sold separately. Not compatible with carbine telescoping assemblies; installing on a carbine may affect function. Safety note Follow all manufacturer installation instructions. Verify proper function and secure mounting before use. Comply with local firearm laws and regulations.