?100% Muslin Cotton?With a deep understanding of babies' delicate skin, Yoofoss has created this sleep sack using 100% organic muslin cotton. This fabric is renowned for its superior softness, breathability, and lightweight nature, guaranteeing optimal comfort for your baby. Additionally, muslin sleep sacks become progressively softer with each machine wash. | ?Intimate Design?For your convenience, we have included a specially designed double-way zipper in toddler sleeping bag, allowing you to easily change your baby's diaper in the night. We use smooth and high-quality SBS zippers, ensuring they won't break even after repeated use. Additionally, the baby sleep sack features zipper protection, ensuring your baby's delicate skin remains comfortable. | ?Freedom of Movement?The design of the baby sleep sacks ensures a perfect fit around the arms and neck, while allowing ample space for the legs. This thoughtful design allows your baby to kick freely without worrying about catching a cold. Not only does it provide comfort, but it also promotes healthy development for your baby's bottom. | ?Ideal Thickness for Sleep?Our muslin wearable baby blanket is designed to be 0.5 TOG, making it the perfect choice for your baby's sleep. Suitable for temperatures between 24-27?/75.2-80.6?, it provides optimal warmth without the risk of overheating. Enjoy longer and more restful sleep for your baby. | ?Best Choice for Babies?With your baby's comfort in mind, we have provided four size options. Size S is appropriate for babies aged 0-6 months, size M for 6-12 months, size L for 12-18 months, and size XL for babies aged 18-24 months. The Yoofoss baby sleep sack is the ultimate choice for finding the ideal sleep sack for your little one, making it a must-have for parents.