Fifteen feet across gives a 13.5 ft jumping mat, room enough for two children at once, and the 331 lb rating in this size backs that up. Four U-shaped foot tubes spread the load on grass and the frame is rust-treated and UV-treated steel. The enclosure net stands 6 ft above the mat, high enough that a jumper cannot go over the top. High-strength PP gives the mat its rebound, and the frame sits 3 ft off the ground. For ages 6 and up. Note that this listing covers 8 to 16 ft frames; the figures here are for the 15 ft version.