SunBusters Boy's Reusable Swim Diapers, UPF 50+ Sun Protection Outer: 80% Nylon/20% Spandex. Lining: 100% Polyester. Imported SunBusters washable and re-usable swimming diapers for babies, infants and toddler boys EXCELLENT SUN PROTECTION: Swimwear fabrics are rated UPF 50+ and provide maximum UV sun protection by blocking 98% of UVA + UVB sun rays, wet or dry; similar rating as SPF for sunscreens. Covered areas don't need sunscreen. Offering 2 layers for the most protection with a super comfy and soft waterproof lining Comfortable elastic waist and legs to assure a great fit, cool and fun prints to match our swimsuit rash guards Bathing suit swim bottoms approved for public pool use