This sleep sack is made with pure breathable soft cotton and we use a pre shrinking process to minimize fabric shrinkage so that the sleep sack could stay cozy warm and soft after every wash. Unlike standard baby wearable blankets this long sleeve sleep sack features foldable mitten cuffs so you can let your baby move freely with the mittens folded down during playtime or flip them up on cooler nights for extra warmth and the cover helps prevent your baby from scratching. Thanks to the smooth zipper at both the neckline and bottom this baby sleeping bag makes diaper change a breeze and you can simply unzip the lower section without needing to fully move the sleep sack. With a roomy design this sleepsack provides your baby more convenience for standing crawling playing or sitting and it is available in multiple sizes for baby growth. These sleeping sacks are machine washable on a gentle cycle.