100% Cotton TWO LAYERS OF BREATHABLE COTTON MUSLIN: made of 100% cotton, double layer muslin, this sleep bag is lightweight and breathable, super soft and cozy for baby to wear, more suitable for air conditioning rooms in summer. comfortable and friendly for baby contacting directly. SEPARATE LEGS DESIGN PROVIDE GREATER MOBILITY: Separate legs design allows room for kicking, but cannot be kicked off so baby stays warm all night, providing greater mobility when your little one is awake, which also allows babies to grow healthier and sleep better. SNAP DESIGN FOR EASY DIAPER CHANGING: snap design on crotch makes diaper changing much easier, it is convenient for baby moving around, never worry about wake the baby up when diaper changing in the midnight. Unzips from the bottom for easy diaper changes. ZIPPER PROTECTOR, SAFE WITHOUT FRICTION OF SKIN: The zipper’s internal protective sheet can prevent the baby from being pulled, and will not rub baby’s skin, super soft and safe for baby. OUR PACKAGE AND SERVICE??Package: You will receive 1 pack BloomStar Muslin sleep bag; We Promise 30-day Money Back Guarantee, if you have any question about the product, please do not hesitate to ask questions.