Flexibility for light speed. For speed in the water and the transition out of it, the Proton range uses light, flexible, hydrophobic materials, suitable for strong swimmers looking for an extra edge on their performance. The Fastskin Proton Wetsuit has been developed with Y38 (Yamamoto 38 cell neoprene rubber) - a well balanced foam providing high buoyancy and flexibility that makes it the most versatile neoprene available - to make sure it performs when it counts. Maximotion+ technology in the single piece chest and shoulder panel means your stroke is as unrestricted as possible.