Features Checks and analyzes motion and speed by simply aiming and synchronizing its flash rate (fpm) with a rotating object RPMs on 4 digit LED display High accuracy over a wide, dynamic range via exclusive microcomputer LSI circuit and crystal control time-base Ideal for measuring the speed of moving gears, fans, pumps, motors and other equipment Tripod mount for stationary use Specifications Flash/Speed Rate: 100 to 10,000 FPM/RPM Accuracy: ±(0.05%rdg +1 digit) Duty Cycle: 5 to 30 minutes Sampling Time: 1 second Dimensions: 8.3 x 4.8 x 4.8" (211 x 122 x 122mm) Weight: 2.2 lbs. (1 kg) Freeze motion and analyze rotating objects without contact. The 461831 checks and analyzes motion and speed by simply aiming and synchronizing its flash rate (FPM) with a rotating object ideal for measuring the speed of moving gears, fans, pumps, motors and other equipment used in general maintenance, production, quality control, or laboratories.