Upper Bounce 8 Pole Trampoline Enclosure Set to fit 12 FT. Trampoline Frames with set of 4 or 8 W-Shaped Legs (Trampoline Not Included). Trampoline Safety Fail? Trampoline Enclosure Set is a must to have to ensure the maximum safety for your kids and their friends. Get this Upper Bounce High Quality Trampoline Safety Enclosure Set so you can relax inside your home while your kids are jumping outside. An essential safety feature for any backyard trampoline. Don"t jump without one.