cotton Imported DESIGNED FOR EARLY WALKERS - Our toddler sleep sack with feet is especially suitable for early walkers and toddlers who are more active during sleep. It gives them freedom to move while still maintaining a comfortable and snug sleep environment. With this sleep sack, you will no longer worry about them getting tangled in blankets or tripping over traditional sleep sacks. BREATHABLE & COMFY FABRIC - The fabric is a blend of premium quality cotton and polyester padding that enhances the permeability, keeps warm and is gentle on baby's delicate skin. It will retain its softness and shape even after repeated washing. It has medium thickness defined as TOG 1.0 that provides enough warmth for cooler nights without causing overheating in warmer weather. UNIQUE CROTCH SNAPS - This toddler sleeping sack has a row of crotch snaps on the crotch that can be fully opened. This feature together with 2-way zipper makes it more convenient for changing diaper. This feature is particularly useful during warmer nights when a little extra airflow is needed. Widened zipper protectors on the top will protect baby's jaw from scratching BOTH FOR SAFE AND COMFORT - Roomy Fit ensures that the sleep sack provides ample room for baby to move their legs freely, what's more is a consideration of baby's growth and hip development needs. A snug fit around the neck and armholes can help prevent the baby from slipping down into the sleep sack. We take careful consideration of various factors to minimize risks and ensure baby's comfort SIZES AVAILABLE - Please refer to our size chart carefully before you order our sleep sack. Extra Small is for 6-12 Months, Small is for 12-24 Months, Medium is for 24-36 Months, Large is for 36-48 Months. This summer sleep sack is certified as TOG 1.0, suitable for nursery temperatures 68°F- 75.2°F. Duomiaomiao 1.0 TOG Super Breathable Toddler Sleep Sack 12-24 Months 100% Cotton Four Season Sleep Sack with Feet, Quilted Comfy Toddler Wearable Blanket