The Ultimate Swim Diaper provides UPF 50+ "Excellent" sun protection and has a waterproof outer layer, extra absorbent inner layer, and wickaway lining next to baby's skin. Snug-fitting legs and waist help contain accidents while in the water. Changes are quick and easy, even when wet! No other diaper necessary, no more bulky disposables! Made from 100% Polyester. Machine wash cold.