Morey Mach 7SS 42 Bodyboard X-Flex System core is a high-tech 100% waterproof core featuring the most advanced polypropylene technology available, comprised of a cross-linked composite material fused between the core and bottom skin, to provide the rider with superior projection, flex and response throughout the entire board CNC contoured deck with knee contours ergonomically designed to help hold your body in place for superior bodyboard control TC8 (8lb density Polyethylene) top skin with Surlyn by DuPont Slick Bottom with grooved slot channels on the bottom skin to help minimize turbulence and increase the boards hold to the waves to increase speed Crescent tail, thumb rails to hold your thumbs to the board for more control and power rod stringer, a dual composite carbon strength tube embedded in the board to give the bodyboard a solid power base The Mach 7SS is the ultimate board for a well rounded rider, the raised thumb ridges provide optimum grip for all sizes of riders and individual hand positions