100% Cotton Imported Premium Fabric: Considering your baby's delicate skin, this sleep sack is made with pure breathable, soft cotton. We use a pre-shrinking process to minimize fabric shrinkage, so that the sleep sack for 6-12 months could stay cozy, warm, and soft after every wash. Foldable Mitten Cuffs: Unlike standard baby wearable blankets, this long sleeve sleep sack features foldable mitten cuffs. Let your baby move freely with the mittens folded down during playtime, or flip them up on cooler nights for extra warmth. The cover helps prevent your baby from scrathcing and keep your little one cozy without restricting their tiny hands. 2-Way Zipper: Thanks to smooth zipper at both the neckline and bottom, this baby sleeping bag makes diaper change a breeze. Simply upzip the lower section—no need to fully move the sleep sack. The thoughtful design is benefit for baby's healthy growth by minimizing sleep disturbance. Besides, our premium zippers won’t snag or get stuck, so you can avoid those frustrating mid-night struggles. Four Sizes: With a roomy design, this sleepsack provides your baby more convenience for standing, crawling, playing or sitting, etc. With 4 sizes, it provides a lot room for baby's growth. It’s wonderful for newborns up to toddlers over 2 years old. It's available for baby 0-3 months or 3-6 months (10-18 pounds), 6-12 months (16-24 pounds), 12-18 months (22-28 pounds), 18-24 months (26-34 pounds). Please kindly see the size chart and choose the fittest size for your little one. Easy to Wash: Throw these sleeping sacks in the washing machine on a gentle cycle! It's really convenient for busy parents who need quick cleanup. To keep the softness of cotton, please always use cold or lukewarm water (no hot water). Made from 100% cotton, the baby sleep sack is more breathable and soft on delicate skin.