On most backyard trampolines the foam surround splits and crumbles long before the frame or the mat gives out. This 15-ft spring cover renews that worn band for a fraction of what a whole trampoline costs. An 11.8-in padded top runs the full circle over 5.5-in springs and a 13.6-ft jumping mat, backed by 0.6-in of high-elastic EPE foam. The outer PVC shell is coated so rain beads off and sunlight does not crack the surface after one season. Elastic ties pull the 8-lb cover tight underneath, and the whole piece folds down small once the weather turns.