The HK MR556 A4 Slimline Buttstock is a factory-original Heckler & Koch component designed to provide a sleek, lightweight, and durable upgrade for your rifle. Engineered for the MR556 A1/A4 and HK416 platforms, as well as standard AR-15/M16 buffer tubes, this stock offers a low-profile design that enhances maneuverability without sacrificing stability. Built from rugged, high-strength polymer with precision fitment, it ensures long-lasting performance in demanding conditions. Its slim contour reduces bulk while maintaining a solid shoulder weld, making it ideal for both professional and civilian shooters seeking a streamlined, ergonomic stock solution.