What are Olympic trampolines made of?

The trampoline consists of a metal frame supporting a spring bed. The bed is made from durable woven nylon material bands and is stabilized with 118 to 126 steel springs on an iron or steel framework. The bed is only about 1/4 of an inch thick. Red vertical lines designed on the net delineate the permissible exercise zone for the athletes. 

What size is an Olympic trampoline?

An Olympic trampoline is 5.05 meters (16 feet, 6 inches) in length, 2.91m (9 feet, 5 inches) in width, and 1.155m (3 feet, 9 inches) in height. 

Strict safety rules demand the placement of large mats, known as the safety platform, on both sides of the trampoline and also on the floor, 2 meters (6 feet, 7 inches) around it. The trampoline competition hall must be at least 8 to 10 meters high (approximately 26 to 33 feet).