The B5 Systems AK stock 4.5mm variant offers a drop-in upgrade for the factory 4.5mm folding stock and mounts by the factory 4.5mm pin to the folding trunnion. It features improved ergonomics, an adjustable length of pull, QD/fixed sling mounts, optic rail cutout and a cushioned buttpad. Proudly made in the USA of composite materials and steel hardware.