An enhanced version of the Magpul CTR® stock, the STR (“Storage/Type Restricted”) buttstock features two 4¼" left- and right-side positioned battery storage tubes and a wider cheekweld for extra comfort. Rubber caps at the rear keep the storage compartments resistant to water incursion, yet pop off easily for access to two AA or two CR-123 batteries inside. Features two integral 1¼" sling loops. Includes reversible QD swivel socket. Friction locking mechanism minimizes wobble between the buffer tube and the buttstock for a solid, secure "feel", which is enhanced by the detachable .30" thick rubber rubber that adds plenty of "grab" to prevent shoulder slippage.