❤SAFETY COMES FIRST-Made from high-quality cotton and superior zipper, Unnivoll baby sleep sack is certified to meet Consumer Product Safety Commission (CPSC) guidelines, eliminate all potential risks and provide a safe sleeping environment for your little one. | ❤UPGRADED PROCESS-Compared with ordinary one, our 100% combed cotton sleep sack brings 30% optimization in both comfort and breathability. Pre-washing technology effectively reduces the shrinkage rate by 50%, which ensures the baby sleeping bag can be machine washed and dried at low temperatures without distorting. We care not only for babies, but also for busy parents! | ❤Long Sleeves with Mitten Cuffs: The wearable blanket's foldable mitten cuffs can be opened or closed to partially inhibit the startle reflex, allowing your baby to self-soothe and sleep better with their hands covered or uncovered. What's more, the foldable mitten cuffs on the baby sleeping bag protect your baby's face from scratches. | ❤EASY DIAPERING-2 way zipper runs from the top to the bottom, making the lightweight sleep sack much convenient to change diapers without any interruption, especially during midnight. Equipped with zippe guard prevent rubbing on your baby's sensitive skin and protects baby's chin. Tog rating 0.5, making it perfect for nursery room temperature 75°F above. | ❤ ACCOMPANY BABY'S GROWTH-Four size options available for your choice, fits baby 0-6 months, 6-12 months, 12-18 months, 18-24 months. Please measure your infant's height and weight, and refer to the size chart before choosing. Unnivoll sleep sack is essential for everyday use, keep your baby cozy and sleeping peacefully!