Dental Handpiece Speed DetectorMade in Japan Order No.: RT-HTM Revolution and frequency measuring instrument Measurement Ranges: Revolution: 5.0krpm to 999.9krpm Frequency: 0.1KHZ to 99.99KHz Revolution detecting method:induction power pick-up system Display:Decimal numeration 4-digit LCD Power Source: AAA battery x 2 Weight:about 140g