Free People Ruby Jacket Shacket Colour name: Jaded This jacket is meant to be worn oversized. Pit to pit difference between each size is 1” so in actuality it doesn’t matter what size you get, it will fit oversized. XS pit to pit is 23” so S is 24” and M should be 25” respectively. I am a size 12 and I own different colours in different sizes ranging from XS to L and they all fit me almost the same way.