Powerball hand held pro gyroscope 250hzstill the fastest gryo on the planet the 250hz range has been certified to 15 000rpm but will clock well in excess of 16k in the right hands these days such is the precision of balance on that 250hz rotor 250hz balls are available with an inbuilt digital speed meter termed 250hz pro or without termed 250hz classicfeatures shell colours amber or blue product weight 262g top speed of 15 000rpm supplied with 2 starting chords instructions