Pocket Radar PR1000 Personal Speed Radar * Uses Doppler radar technology * No calibration is needed * Portable design with a rugged casing * Memory recall of up to 10 previous speeds * Battery life of more than 10,000 readings on two AAA alkaline batteries (not included) * Range under good radar conditions (results may vary): baseball from 120 feet and car from 0.5 miles * Accuracy within one mile per hour * 24.125 GHz operating frequency * Measures from seven to 375 mph