100% Cotton Imported 100% Premium Cotton: Made of 100% cotton to guarantee the utmost comfort and the protection of toddler's sensitive skin. Yoofoss baby sleep sack with sleeves is certified to meet Consumer Product Safety Commission (CPSC), dedicating to ensure your baby's safety and coziness. Long Sleeves with Mitten Cuffs: Long sleeve baby wearable blanket minimizes the chances of becoming chilled, ensures free arm movement and warmth for your little one when napping in cool summer A/C room and sleeping at chilly spring,autumn and winter nights. What's more, this baby sleep sacks with eversible mitten hand covers can be adjusted according to temperature, ensuring the baby's hands stay warm. 2-Way High Quality Zipper: Double zipper allows for easy dressing and convenient diaper changing with no hussle and bustle. With top-grade zippers and zipper flat design, sleeping sack for baby frees from any potential scratches, glide along the tracks moothly without any snagging or jamming. Safety Sleep: The neck opening is precisely tailored to provide a snug fit. Wide hem is thoughtfully designed to allow baby to move freely but not kick off, keeping newborn warm throughout the night. This sleep sack for baby play a vital role in nurturing optimal hip development. Available Size and Mahchine Washable: There are 4 sizes available sleep sacks for your choices; S for 0-6 Months, M for 6-12 Months, L for 12-18 Months, XL for 18-24 Months. Please measure your infant's height and weight, and refer to the size chart before choosing. This long sleeve baby sleeping sacks withstand multiple machine washes and reduce the household chores for parents. Made of 100% cotton to guarantee the utmost comfort and the protection of toddler's sensitive skin.