The one that started it all: Our most-loved, best-selling sleep bag. A wearable blanket that helps baby fall asleep (and stay asleep), so you’re not up all night. Designed to be safe sleep, diaper change friendly, temperature-regulating, and so soft you’ll have to touch it to believe it. Exterior: 97% Rayon made from Bamboo, 3% Spandex Highly breathable J-shaped double zipper Due to lack of quilting the 0.5 TOG Sleep Bag tends to run bigger and have more stretch. We recommend a thicker tog during cooler months and a thinner size during warmer months. .5 tog made for rooms in temperature range of 74-78 degrees Sleep Bag Sizes are based on the weight and size of your infant. Our sleep bags are made longer to give your infant lots of room to kick and grow. When deciding on the right fit for your child we recommend ensuring the neck and arm holes are snuggly fit to baby and the fabric cannot ride up over babies airway. Fit chart: Size S - 14-20 lbs weight, 22-27" height Size M - 18-30 lbs weight, 26-33" height Exterior: 97% Rayon from Bamboo, 3% Spandex Filling: 100% Polyester