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. EXCEEDS SAFETY STANDARDS: 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. EASY DIAPER CHANGE: Reversed zipper allows quick and discrete diaper change without disrupting baby's sleep. COMFORTABLE: Your little sweetie will be able to move freely in the crib thanks to the sleep bag's wide bottom. Coziness guaranteed no matter baby's favorite sleeping position.