The overall frame of the small soft board is made ofaluminum-magnesium alloy, the spring is a German spring, and theweight of the spring can be customized freely; it uses European superfiber leather pads, filled with EVA cotton, which will notcollapse or deform, the Japanese imported raw material polymer ultra-quiet wheels ensure smooth operation Silent, nobumps; automatic rope retracting function; headrest adjustable in three positions; customizable standing platform;special tensile pulley for sailboats, can with stand 500 kilograms of force; 2 imported nylon ropes, soft and delicate,exquisite workmanship, maximum Pulling force up to 600kg