The Q Shorty Stock is a 2-position, low-profile PDW-style stock for AR-15 / M4 builds running a standard mil-spec receiver extension. Designed for short-barreled rifles, pistol builds, and home-defense rifles where overall length matters. Fit: AR/M4 receivers with mil-spec diameter buffer tubes (commercial-spec tubes will not fit). Features: 2-position adjustment - closed and extended lock points Integrated locking back plate eliminates rattle on the tube Integrated QD swivel socket for ambidextrous sling attachment Sleek low-profile geometry for PDW configurations Includes carbine recoil spring and 3 oz buffer Gray finish. Best paired with a mil-spec carbine receiver-extension tube - verify your tube diameter before install. Drop-in for any standard AR/M4 lower.