The Magpul STR (Storage/Type Restricted) Carbine Stock – Mil-Spec is a drop-in replacement buttstock for AR15/M4 carbines using Mil-Spec sized receiver extension tubes. A storage-capable version of the CTR®, the STR offers an improved cheek weld and two water-resistant battery tubes within a compact, reinforced polymer A-frame design.

A shielded operation lever and supplemental friction locking system help prevent accidental operation and minimize stock movement for enhanced weapon stability and accuracy. The STR also includes two integral sling loops, a reversible push-button QD sling mount, and a replaceable 0.30″ thick rubber butt-pad which ensures positive shoulder purchase and prevents slippage, even with body armor or modular gear.