95% Rayon derived from Bamboo, 5% Spandex Imported Safe and Comforty: Our baby swaddle are tested by professional testing institutes and comply with CPC standard for baby products. The swaddle blanket is 95% rayon derived from bamboo and 5% spandex, which is known for its softness, sustainability and friendly to baby's skin Care for Baby's Development: Loose hemlines be beneficial for hip development in babies by allowing for greater freedom of movement and flexibility in the hip joint. Aomloge swaddles for newborns pay more attention to the development of baby's bones, ligaments, and muscles in the hip, ensuring that they grow up with strong and healthy hips Relieving Parents' Stress: Baby's sleeping problems are really troubling to every parent. Swaddle sack can simulate a mother's embrace by wrapping a baby securely with only the head exposed to give your baby a sense of security and soothe them when they're fussy or upset High Quality Zippers: Our zips have been repeatedly tested 10000+ times to ensure smoothness in use. Easy to put on and take off with 2-way zipper. 20% more in length make it more conveniently to change nappies Localised Fit Design: To design this transition swaddle, we have researched the majority of American babies' height, weight, shoulder width, chest circumference and other various parameters, and also referred to the official data of the WTO organization. This baby swaddle is a perfect choice for babies 0-15 months with 4 sizes