I'm not quite sure what size I would be in a binder. I've done the measurements and worked out that I'm 31" chest, but the binder I'm going for (Style 997 at Underworks) goes from XS 29-31 to S 32-34. As I'm on the large side of the XS, should I go for a S? I'm afraid incase I go for the XS and it might be too small and I won't be able to breathe properly at all xD As I am on the bigger side of an XS. I've never bought a binder off Underworks (heck, at all even) and was wondering whether it might be too tight to go for an XS and whether I should go for a S.
What are your thoughts? XS or S?
(First post by the way

Hey guys! I'm awful at explaining things so sorry if this seems silly).