The latest offering from KAC is the URX IV. The URX IV is a continuous top-rail system that utilizes the Keymod mounting brackets developed by Vltor and Noveske.
The idea was to create a more modular, and thus more serviceable, rail system that still maintains its strength and stiffness. The modular layout allows an end user to fully customize exactly where to place accessories without the use of specialized tools, small parts, or additional forces applied to the barrel. A full array of modular accessories, iron sights, and panel kits utilizing the Keymod mounting brackets have been developed specifically to accompany this rail system. With the introduction of the URX IV, Knight’s Armament Co. demonstrates its continuing determination to intelligently design effective products.