Its a good quality fabric, good model lab coat. But sizing is interesting.
I am XS in GAP, usually XS-S in other brands. Never ever an XXS.
FYI: 5'4", 117 lbs, 32 A or B (depending on model), waist 26, bottom 34'.
I really like snug fit and I bought this lab coat for job in office (not much holding hands up, carrying, hands manipulations), cause XXS fits very good everywhere, except biceps area, its little too snug, I can still lift my arms, but the sleeve is very tight (I include the photo where). I don't want to go size up, cause everywhere else it is good, only one layer shirt, no sweater will do. So not going to give back as it fits for my job, but if I needed it in a lab, where many manipulations with arms needed, I would go size up. Hope it helps.