100% Cotton. Tagless Label to help protect your child's delicate skin. Machine wash cold, inside out. Your child will be comfortable and cool in Leveret cotton short sleeve pajamas. Available in a variety of colors, prints, and stripes. As a natural product, cotton may shrink 1-3 inches after washing. These pajamas are designed to fit snugly for fire safety reasons. We recommend sizing up if your child is above average.