This 0.7 TOG sleep sack is just perfect for spring and summer. Made of breathable, light 100% cotton muslin, it is soft on baby's skin. Plus! It will get softer every time you wash it. The Perlimpinpin wearable blanket will keep baby comfortable for a nap or through the night. This fabric allows airflow, helping reduce the risk of overheating. It is suitable for warmer temperatures or for colder ones with proper sleepwear. Using a sleep sack clears blankets from the crib which can interfere with the baby's breathing. Perlimpinpin baby sleeping bag are perfectly adjusted to fit the neck hole and opens only from the bottom ensuring the bag is never over baby's head. It’s reversed zipper allows quick and discrete diaper change without disrupting baby's sleep.