This cuddly long-sleeve one piece just begs for snuggle time. One long zipper makes getting dressed a breeze, and the soft footies keep little toes warm when the temperature cools. By adding 5% spandex to natural cotton muslin, Aden + Anais turned a wonder fabric into a super fabric, adding just the right amount of stretch to a soft, comfortable essential that will keep baby warm without overheating. Plus, just like their other muslin products, your long sleeve zip one-piece will get softer with every wash. Soft: pre-washed for baby?s comfort, and built to last ? our items get softer with every wash; Stretch: 5% spandex gives each item just the right amount of one-way stretch; Breathable: keeps baby comfortable without overheating; Covered zipper: keeps zippers away from baby?s soft skin; 95% cotton muslin, 5% spandex;.