KGM R556A1, Suppressor, 556NATO/6MM, 4.85 Long, Inconel Hardened Stainless Steel Construction, 1/2x28 QD Flash Hider, C-Series Cerakote Finish, Black RS-R556A1-QD-BLK The KGM R556A1 is a compact yet robust suppressor designed to meet and exceed SOCOM specifications for full-auto firing, accuracy, repeatability, sound suppression, and minimal impact on a rifle's operating system. The R556A1 has successfully surpassed over 20 SOCOM SURG firing cycles and continued to perform. The R556A1 works on 5.56 rifles of every barrel length, and is ideal on 14.5" and longer barrels. Beginning summer 2024, the R556A1 has the bore EDM cut open to accommodate 6mm cartridges such as the 6mm ARC.