B5 Systems Collapsible Precision Stock - Long - Black - The B5 Systems Collapsible Precision Stock (CPS), Long. Building upon the venerable cheek profile of the B5 SOPMOD and Bravo stocks, the Precision stock incorporates an adjustable cheekpiece and buttpad while fitting Mil-Spec carbine receiver extensions. Features internal tensioners, ambidextrous fixed and quick disconnect sling mounts, gross length of pull adjustment via pull down with lockout, underside M-LOK accessory mount, and color matched hardware. The CPS Long is optimized for side charging and rifles equipped with the LAW side folding adapter.