PTS UBR™ Collapsible Buttstock The Magpul PTS UBR™ (Utility / Battle Rifle), U.S. Patent 6651371, is a fully-featured, adjustable butt stock for AEG M4 / M16. Unlike typical collapsing stocks, this modular design offers the stability of a fixed stock with consistent cheek weld in any position. Seven-position length-of-pull (LOP) adjustment is quickly executed with gross motor movement while the integral preset system allows direct access to a preferred position. The UBR™ also provides extra counterbalance weight to improve handling on full-length rifles and weapons with muzzle-heavy accessories or grenade launchers. Optional components such as dual-side sling mounts and metal strike plate allow the UBR™ to adapt to the mission at hand. Features - New design Receiver Extension tube which fits Lipo Battery.- It fit short type AEG receiver only.- 7-Position LOP adjustability with customizable preset system for fast access to preferred length- Made by DuPont™ Polymer with Reinforced Stock Body (Steel plate)- Solid “fixed stock” lockup in all positions- Repositionable cheek piece accommodates users requiring extra eye-relief- Stout construction provides counterbalance weight for improved weapon balance and handling- Sling Mounts- Front / Rear - push-button QD sling mounts - Bottom - 1.25" Sling loop Included Accessories - Storage Module (Left-Right Reversible / Removable)- Rubber Butt-Pad, 0.30” (Removable)- Front / Rear – dual side push-button QD sling mounts