Koson-Man Men's Sports Soft Fashionable Lace-up Swimming Underwear Strips Trunks polyester Material:Made of waterproof material.82% Nylon,18% Polyurethane. Soft and breathable material make you comfortable when you swimming. Closure:Lace-up.You can tie up in your mind.The best level to make you comfortable but not tighten. Due to the material, please wash with cold water.Warm water will damage the trunks. We usually suggest our customers order on size up than normally wear due to Asian size.If you still have any questions,dont hesitate to contact us.