This baby sleep sack is made with organic cotton super soft and breathable for comfort and the sleeveless design helps regulate baby temperature reducing overheating risk and ensuring warmth and cozy. These baby sleep sacks are CPSC certified for your baby safety and comfort and the neckline has been carefully sized and numerous experiments ensure a secure and snug fit preventing the baby from slipping into the sleeping sack and the loose around the legs allows for natural hip development. This light weight sleep sack is suitable for moderate temperatures as an ideal option for spring summer autumn or taking a nap in air conditioned rooms keeping your baby snug and warm. Our baby wearable blanket features a double zipper so you can unzip from the bottom to change diapers and disturb baby even less during the night and zipper protectors on the top will protect baby jaw from scratches.