Super-Ball by Wham-O

Super-Ball by Wham-O on Ebay
Super-Ball The Super-Ball (or SuperBall) is an extremely bouncy ball invented by Norman Stingley, and manufactured by Wham-O starting in 1965.

It is an extremely elastic ball made of Zectron, which contains the synthetic rubber polymer polybutadiene, vulcanized with sulfur at a temperature of 329 °F and at a pressure of 80 standard atmospheres (1,200 psi). The Super Ball has a very high coefficient of restitution. Dropped from shoulder level, a Super Ball will bounce nearly all the way back; thrown down with sufficient force, it can leap over a 9-story building.

The Super-Ball rebounds proportionally to the amount of force used when thrown at a hard surface. A typical Super Ball can keep around 80% of its kinetic energy in one rebound.

Generic bouncing balls are often sold from bulk vending machines for 25 cents or more.