The AirzoneĀ® 14-ft Spring Trampoline and Enclosure Combo is safe and fun way to exercise. The trampoline has a rust-resistant steel frame, six "W" shaped legs, steel springs, and a weather-resistant mat and frame cover. The enclosure (color may vary) is designed with 6 padded steel poles for maximum safety and finely knit mesh netting with a zippered entrance door for added security. Both were tested to meet ASTM safety requirements.