Michael C Liftfoil? with coldBlack? Technology ? At speeds below 5 mph (8 kph) the best surface to flow though water is a smooth surface like Liftfoil. Liftfoil is a hydrodynamic fabric designed to be worn very tight. When stretched on a moving body, Liftfoil becomes thinner, so it absorbs less water. Because it compresses against the skin, it reduces passive drag, and acts as a foil to lift the body at the water surface. coldBlack? Technology Sun Reflector ? UV Protector: Dark colors heat up stronger when exposed to direct sunlight compared to light colors. This no longer needs to happen! Now there is coldblack ?, a special finishing technology for textiles which reduces heat build-up and provides reliable protection from UV rays. coldblack ? technology offers two innovative benefits: 1. Effective heat management - Light colored textiles reflect both visible and invisible rays of sunlight, meaning both heat and light. Dark colored textiles absorb both types of rays and therefore absorb heat. coldblack ? reduces this absorption of heat rays, particularly in the case of darker colors, and in all types of textiles. The result is tangibly better heat management. Because textiles finished with coldblack ? heat up less in all colors compared with material without a coldblack ? finish. 2. Reliable protection from UV rays - The coldblack ? technology guarantees a minimum UPF 30 protection (blocks 70% of UV rays) when applied to any textile in any color without affecting the look or feel of the product. As a result, textiles with coldblack ? can make an effective contribution to protecting against harmful UV rays. You would probably be in a size medium.