FAB Defense GL-Core Buttstock w/Adjustable Cheek-Rest is a matte black fiberglass reinforced polymer collapsible buttstock for AR-15/M4 platforms, fitting Mil-Spec or Commercial buffer tube diameters via included interchangeable buffer tube adapters. Features an integrated cheek weld, ergonomically shaped rubberized buttpad, two integrated QD rear sling swivel connectors, an inverted positioning lever, and an additional 3-position adjustable cheek rest designed for optics/holographic sight use on AK, VZ, and shotgun platforms. Note: on AR platforms, the cheek rest may obstruct charging handle use when fully collapsed; removal is recommended for AR use. OAL 7.08, height 6.02, width 2.16. Weighs 14 oz. Safety note Follow all manufacturer installation instructions. Verify proper function and secure mounting before use, especially when using the cheek rest on AR-platform rifles, as it may obstruct charging handle operation when collapsed. Comply with local firearm laws and regulations.