SwimZip Big Boys' Swim Trunks with UPF 50+ UV Sun Protection Drawstring closure Rated UPF 50+ ... Blocks 98% of UVA and UVB Rays! (Called UPF 50+ for fabric). The highest UV sun protection rating for fabric! Adustable drawstring waist. Mesh lining inside the swim trunks. Soft comfortable, quick dry material. Highly chlorine and salt water resistant fabric. Super cute, award winning styles! Products featured on Prime Time National Television show to audience of over 6 million people.