Engineered for Endless Sunny Play: Avensea UPF 50+ Cooling Boys Rash Guard At Avensea, we are dedicated to making every beach moment cooler and safer for kids. This long sleeve rash guard is crafted with 14 years of specialized expertise, featuring instant cooling fabric that keeps boys comfortable through every sun-soaked adventure. Better Cool with Instant Cool​ – our COOLMAX technology quickly pulls moisture away, spreads it evenly for balanced cooling, and uses rapid evaporation to maintain active breathability. The UPF 50+ fabric provides superior UV protection that works even when wet, blocks 99.9% of harmful rays, and is made for long hours of play—not just sun protection. Designed with 4-way stretch for full freedom of movement, it's lightweight, quick-drying, and gentle on skin. Whether it's surfing, swimming, or beach play, this rash guard is the trusted layer that keeps boys cool, dry, and protected all day long. Available in sizes for toddlers to teens, it's more than a swim shirt—it's peace of mind in every sunny moment. Choose Avensea, where innovation meets summer fun.