The CMMGRipStockis a revolutionary, retractable buttstock engineered for lightning-fast deployment to your personal setting. With our FastbackTechnology, you simply pull straight back to extend the brace. No locking tabs to release or bind. P3 (Personal Position Preset) offers multiple customizable length presets to ensure the stock extends to your personal position every time it is deployed. Simply adjust the indexing screw on the buffer tube to customize your preset.Aircraft grade aluminum construction offers superior durability without adding unnecessary weight, and a premier Cerakote finish let you customize the color to fit the look of your AR. Backed by CMMG's Lifetime Quality Guarantee.Kit Includes:RipStockFastback 6-position Receiver Extension (Buffer Tube)Castle NutAmbi Sling Mount Receiver EndplateAR15 Carbine BufferAR15 Carbine Action Spring