It's SUPER-SOFT bamboo!
Long enough to tuck into jeans to keep your back warm.
Would make great sleepwear.
Although people seems to complain that these tops are too small for their sizing, I found the 10-12 to be enormous on me. Really loose around the belly (which for some might be a plus?) and the shelf bra really loose and unsupportive as well. (For reference I am on the small side of a size 10 and cup B/C). Luckily my boobs are small enough not to need too much support, so in this aspect I could have gotten away with it, but even though bigger boobs would fill it out better, I still doubt it would offer enough support except as sleepwear. Also because it was too big, I found the neckline scooped down too far falling below the shelf bra and top of the "peep-holes" which looks rather ridiculous and indecent!
Also, which is a BIG factor for me and nobody ever seems to mention in reviews, the "peep-holes" (circular cut-outs in the shelf bra for breastfeeding) are really big, revealing your entire breast. There is only the most minimal stretch of material that sits above your breast (1cm at most), with no discreet flap of material covering the top of your boob. So not at all discreet for public feeding.