The Gold Hyper-Spin has been used to win more Olympic Medals and set more records than any discus in history. Uses a machined bronze rim with up to 84.5% rim weight and capable of being thrown the farthest because it can sustain a high rate of spin throughout its flight. Intended for top level throwers. Meets all IAAF, NCAA & NFHS specs and is IAAF certified for international competition.