Pure cotton,soft and comfort Package included: 6-pack pieces of series undies Fabric-encased leg opening and waistband for comfort Sizes 12, 14, 16, 18: Customers report these run smaller than expected. Due to the limited stretch of 100% cotton fabric, we recommend sizing up 1-2 sizes for a better fit. Care Instructions‌: Machine wash cold with similar colors. Use non-chlorine bleach if needed. Do not iron. Wash in cold water and dry on low heat/gentle cycle. Winging Day kids underwear, quality cotton,soft and comfort， let you no worries and buy safely , a variety of interesting and vivid patterns, bring joy to your children.