Our buttery soft & stretchy Back Zip Bags are designed to be comforting AND hard for your child to remove at night and during naps. Made from eco-friendly fabric our light-weight wearable blankets/sleep sacks are designed with zippers in the back and reinforced binding along the neck and arm holes so that your toddler can't easily wiggle their way out. The material is very stretchy so that your child can easily stretch and move their legs freely. The arm and neck holes are designed to be comfortable but form fitting to prevent your child from easily removing the sleep sack. Our wearable blankets are made in the USA with fabrics that are free of harmful chemicals (OEKO-TEX certified).