I got an XL because I have a 40DD chest, which is hard to fit in a tank-top style, but the Hanes Women's Ribbed Tank fits great and runs true to size. The length is 33", which I also like, because wearing it scrunched up around your waist creates a ruching effect that is very flattering. The hem is not stretchy; these are 100% cotton undershirts of the 1950's starchy variety, not soft, absorbent Peruvian Pima cotton. The tighter hemline is what allows the ruching effect when it's hiked up. The back at the shoulders is a tiny bit blousony, but I'm sure it will become more fitted after it shrinks in washing. These are also tagless, so no scratchy label at the center of your back.

The all-cotton (the 7% Nylon description is incorrect) rib is thin but only a bit sheer. You may not want to wear the white by itself, however I've found almost all the other colors Hanes offers (charcoal, salmon, black, blue and light grey)in this tank to be perfectly acceptable as a stand alone top. I find it flatteringly long, shape-definingly fitted and comfortably light and breathable.

By the way, the XL also fit my boyfriend, who's a 42 long, perfectly. Paired it with a an open button-down shirt.