Skywalker Trampolines 17&rsquo; Oval Trampoline with Enclosure and Wind Stakes &ndash; Blue Although not required by law, all Skywalker Trampolines products are thoroughly tested for safety and durability, and are found to meet or exceed all standards put forth by the American Society for Testing and Materials (ASTM). Includes 4 galvanized steel wind stakes to help keep your trampoline anchored during inclement weather Unique Oval shape provides longer jumping surface Patented no-gap enclosure system eliminates gaps (Patent #RE45, 182) Reinforced T-sockets increase the stability and prevent structural twisting Weather and rust resistant galvanized steel frame construction Jump mat is made of UV protected polypropylene, woven to prevent slipping 96 rust-resistant springs, 7" long Extra thick vinyl-coated spring pad is fade resistant Enclosure net is made of tightly-woven polyethylene, providing UV protection