These are made out of soft, but thin material. I wash mine on the gentle cycle. I wanted a thin cami that I could tuck into my pants and not show the world my backside. These come down over my butt and I'm 5'9 in medium. I always wear a shirt over these so I didn't want a built in bra liner. To summarize...

Don't buy if:
you want a bra-liner
you want a cami in a thick material

Do buy if:
you want a cami soft enough to be a night shirt
you want to wear a shirt over this
you want to cover your crack