Hocosa Baby Onesie in 100% organic merino wool provides natural warmth and protection. Wool is nature's perfect fabric as it offers warmth without heat build-up as wool is breathable. When babies are warm they feel comfortable and safe. Babies who are warm thrive and grow well. The onesie can be paired with a matching long john for added warmth for sleep or play. Wash by hand or machine washable on gentle cycle in warm water.