Because of its lightweight, polypropylene is the only rope which floats and for this reason is very popular for use as pool markers and water sports. Polypropylene is affected by sunlight deterioration, but its life can be extended by storing it away from direct sunlight. Polypropylene begins to weaken at 150 deg F and melts at 330 deg F, the lowest melting point of all synthetic ropes. It is generally an all-purpose rope for the average consumer.