Used only a few times before my baby outgrew this size. Description below is taken from the brand's website: YOUR BABY'S SNUG HUG FOR SAFE AND SOUND SLEEP Give your baby the gift of better sleep with the Swaddle Sleep Sack, the world's first 3D knit seamless swaddle. It provides the perfect blend of comfort, safety, and freedom, creating an ideal environment for serene and self-soothing sleep. As your child grows or starts to roll over, it easily transitions into a wearable blanket for increased movement, just leave their arms out to ensure safety and comfort. This feature makes the Swaddle Sleep Sack a thoughtful and practical gift for new parents. Our Hug Technology® gently cradles your baby to self-soothe through Moro reflex and active sleep, encouraging a deep sense of calm. Designed in compliance with AAP guidelines, the Swaddelini ensures a secure fit around the chest and appropriate looseness around the hips for safe and comfortable infant care.  In this Swaddle Sleep Sack, your little one spends each night in comfort and safety, warmed by the echo of your caring embrace with the innovative design of Hug Technology®. SOOTHING COMFORT IN EVERY FIBER Expertly crafted from soft, sustainable, eco-friendly, post-consumer recycled nylon. A gentle touch that’s also durable. Moisture-wicking capabilities ensure dry, comfortable nights. Proudly crafted in the USA to the highest standards of quality and environmental care.