The RS9 is a light weight, full auto rated, 9mm suppressor designed around blow-back style pistol caliber carbines. With special design features to reduce the dreaded "port-pop" you hear on typical blow back style actions. The RS9 features a complete 17-4 Stainless steel baffle stack. Compatible w/ Keymo (DA428), Rearden Atlas & Atlas XL, Plan B, ASR (AC824), JMAC X37, YHM Kurtz (YHM-3051), YHM Tri-Lug (YHM-2045) RESILIENT RS-RS9 RS9 9MM 1/2X28.