The 50” tube is the preferred choice of the American Red Cross and the standard rescue tube used by guard training agencies. All Kemp USA Rescue Tubes are made of the highest quality closed cell foam to resist erosion. They are individually hand dipped three times instead of the customary two to ensure proper adhering of the vinyl coating and extend the useful life of the equipment dramatically. Our adjustable shoulder strap and tow line consists of durable nylon webbing and runs through the entire tube.