Made from black polyethylene. Research over the years has shown that swimming pools that are not emptied in winter survive the season better. Frost cannot penetrate the side walls or ground and rain water cannot cause any damage to the floor. However because of the frozen surface, there is great pressure on the sides of the pool. By hanging ice pressure pads on the long and front sides of the pool, the pressure in reduced and therefore damage is reduced. Exclusive to Sport-Thieme. Made from resistant polyethylene. The body of the float is sealed and the ballast boxes are filled with quartz sand for stability. LxWxH: 50x32x approx. 4 cm. Coupling links for joining the pads to each other are also included.