2 rail. I have shot 18s with rifle fuel like how easy and precise they are. I can set extra money into general performance parts then clone accurate sections similar to a ops brake and collar that I haven't got a can for. Over time the Maritime Corps did approve https://kacquadrailcarbine63060.vblogetin.com/35088511/indicators-on-kac-ras-m4-you-should-know