SwaddleDesigns Cotton Knit zzZipMe Sack is a soft wearable blanket, perfect for babies that are ready to graduate from swaddling blankets. Our zzZipMe Sacks feature a 2-way zipper which zips down from the top, making it easy to place baby into sack, and also zips up from the bottom, keeping baby snugly warm during diaper changes. So easy. This cotton knit zzZipMe Sack has a TOG rating of 0.7, which is best for temperatures of 72-78 degrees F, to keep baby comfortable in warmer weather. Sizes: Small up to 28 inches (71cm) ; Medium up to 32 inches (81 cm); Large up to 35 inches (90 cm). Coordinates with many of our high-quality baby essentials. Machine wash. Made with love for the little one you love.