CPSC Safety-Certified for Ultimate Comfort - Our 3-pack sleep sacks are CPSC certified to safely replace loose blankets. Made from 100% breathable cotton that is super lightweight, non-polluting, and gentle on sweaty skin, they ensure a cozy sleep environment. Featuring extremely low water shrinkage per lab tests and easy machine washability. 2-Way Zipper Style - We adopt smooth 2-way zipper with whole interior zipper guard and widen top zipper cover to protect baby's sensitive skin. Unziping from bottom up makes it easy to change diapers without any interruption, no worrying about your baby catching cold. Let your baby have a peace sleep all night! Security is Our Top Priority - The neckline is well designed based on physical development of a baby at different months of age. There is no potential danger to the baby that may cause suffocation or rub baby's delicate skin repeatedly because the neckline is too large or too small. The size of the cuff also ensures that the baby will not easily get out off. We pay attention to every stitch and seam to ensure the durability of our products. Lively Pattern Story - Multiple researches indicate that bright colors and lively printed elements can positively promote the development of babies' brain and vision, especially for their attention and imagination. Our sleep sack is printed with lovely and interesting patterns. We always hope to do more for baby's development. Baby Essentials - We believe that newborn essentials must have such a beautiful 3 pack summer sleep sacks. They come in 3 sizes, S for 0-6 Months, M for 6-18 Months, L for 18-36 Months. These colors are suitable for both baby boys and girls, which is perfect as baby registry. Duomiaomiao 3 Pack Baby Sleep Sack 100% Organic Cotton 0.5 TOG Lightweight Breathable Comfy Toddler Sleeping Sack