So I did some research and I also did not find any M4V9 with an 18in bbl. I am contacting Daniel Defense and asking them why they sold me one with an 18in bbl and I’ll let you know the outcome. Thanks for pointing that out.
It’s a V9 S2W.... Daniel Defense only made them for 2 years... V9 S2W only came with a 18 S2W barrel. You won’t find it on DD’s website because they don’t make them anymore. They were replaced with the PRO line