The O'Neill mens Reactor II sleeveless wetsuit is engineered for performance in a value driven package. A fresh combination of stretch and durability. Fresh colors and graphics with style that's built to last. FluidFlex™ neoprene A category of high stretch neoprene with an ultra soft hand and insane affordability. Stretch factor: 100% Flatloc stitched The most popular method of sewn construction. The stitch uses 4 needles and 6 threads, and works by overlapping the neoprene panels and sewing them together. It is a strong stitch and is very comfortable because it is flat, but it is not a sealed seam so it is not intended for extremely cold conditions. Strategic seamless paddle zones An ergonomic, seamless under sleeve panel that allows for unrestricted motion and eliminates rashing. Flexible and unique design which utilizes minimal seam placement for comfort. Krypto knee padz Abrasion resistant, high stretch neoprene panel with ergonomic shaping for comfortable durability. Flexible and unique design utilizes and extended knee pad for added durability.