Magpul Industries CTR Stock, Fits AR-15, Adjustable, Black MAG310-BLK The Magpul CTR (Compact/Type Restricted) - Mil-Spec Model is a drop-in replacement buttstock for AR15/M16 carbines using mil-spec sized receiver extension tubes. Designed for light" fast action the streamlined A-frame profile avoids snagging and shields the release latch to prevent accidental activation. The CTR also features a supplemental friction lock system that minimizes excessive stock movement for enhanced weapon stability;and an ambidextrous QD sling mount that will accept any push-button sling swivel. The Mil-Spec Model includes a standard 0.30" thick rubber butt-pad which provides positive shoulder purchase to prevent slippage even with body armor or modular gear.