The Original Trick Disc! Duncan® Sky Spinner® is a ground breaking, hand-propelled spinning disc. Unleash an awesome array of tricks and stunts; throw it, crank it, spin it or slam it. Use the power crank to get your Sky Spinner® spinning with the flick of a wrist. With a perfectly balanced, weighted rim, it can reach an incredible 500 revolutions per minute. Easy and fun for all ages to use!