Features • Mounts on durable Entry-Length Receiver Extension tube (included) to accommodate the common M4 carbine buffer and spring • 7-Position LOP adjustability with customizable preset system for fast access to preferred length • Adjustment lever requires only gross motor movement to operate yet the entire stock remains streamlined and anti-snag • Solid "fixed stock" lockup and consistent cheek weld in all positions • Enhanced lock mechanism w/ internal impact buffer increases drop strength and shock resistance • Multi-shell construction provides solid foundation and shields critical operating parts from penetration damage • Sloping cheek weld combines a slim profile with user comfort • Stout construction provides counterbalance weight for improved weapon balance and handling • Storage compartment in tail of stock is removable and the door is reversible for user preference • Removable 0.30" Rubber Butt-Pad offers an anti-slip surface and increased impact protection • Sling Mounts • Front/Rear - Reversible QD swivel sling mounts fit up to 1.5" push-button swivels (swivel not included) • Bottom - 1.25" sling loop Optional Accessories• Extended Rubber Butt-Pad, 0.55" • Enhanced Rubber Butt-Pad, 0.70" • Aluminum Strike Plate w/ 1.25" sling loop • Dual-side push-button QD Swivel Sling Mounts Specifications• UBR Collapsible Butt Stock • Weight: 1.46 lb. • Weight, w/ Entry Receiver Extension: 1.63 lb. • Length, Stock: 8.00-11.36 in. • LOP Adjustment: 7-Position (0.56 in. / position) • LOP Adjustment Range: 3.36 in. • LOP, Collapsed (M4/M16): 11.10 in. • LOP, Extended (M4/M16): 14.46 in.