The Extech 461825 is two meters in one — a stroboscope for speed and motion analysis of rotating objects plus a non-contact tachometer to measure RPMs. The Extech 461825 photo tachometer / stroboscope features a large 5-digit display with characters that reverse direction depending on which measurement mode is active. The Extech 461825 photo tachometer / stroboscope is microprocessor-based with quartz crystal oscillator to maintain high accuracy. Battery operation brings motion analysis to any location.

The stroboscope function of the Extech 461825 photo tachometer / stroboscope has course and fine flash rate adjustments in three ranges to freeze and analyze rotating objects. It is capable of measurements from 5 to 99,999 RPM with an accuracy of Accuracy ±0.1% +2 digits and a resolution of 0.1 FPM for speeds under 1000 FPM (1 FPM resolution for speeds above 1000 FPM). Sampling time for the stroboscope is 1 second for speeds at or above 60 RPM.

The photo tachometer function of the Extech 461825 photo tachometer / stroboscope has a memory function that stores last, max, and min readings. The tachometer has a range of 0.5 to 20,000 RPM and 0.2 to 6560 ft/min. The resolution is 0.1 RPM for speeds under 1000 RPM (1 RPM resolution for speeds above 1000 RPM). Sampling time for the tachometer is 1 second for speeds at or above 6 RPM.

The Extech 461825 photo tachometer / stroboscope ships complete with meter, four 1.5 volt AA batteries, reflective tape and carrying case.