This 9/16\" x 50\' tube rope has a 3/8\" bungee cord spliced inside. It\'s 4,150 lb tensile strength conforms to WSIA recommendations for 1-4 rider tubes. Youll enjoy brief surges of speed as the bungee stretches and contracts. It reduces wear and tear on tubes and riders by absorbing sudden jerks from slack in the line. Includes a Rope Keeper.