Thermo-X Long Sleeve Thermal Top for Water Sports The Thermo-X Long Sleeve Top is designed for water sports enthusiasts who need extra warmth and protection on cooler days. It can be worn as an insulating base layer under a wetsuit or on its own as a comfortable long sleeve water sports top. The technical Thermo-X Hyperdry fabric helps retain body heat while remaining lightweight, flexible and comfortable. Its four-way stretch construction provides excellent freedom of movement, making it ideal for surfing, stand-up paddleboarding, kayaking, sailing and other water-based activities. With UPF 50+ sun protection, the Thermo-X top provides maximum protection against harmful UV rays. Strategically placed ergonomic seams and flatlock stitching help reduce friction and irritation, ensuring a comfortable fit both under a wetsuit and when worn on its own.