Used for contact or non-contact measurements, the members of the HHT10 multi-function tachometer family fit in a shirt pocket and weigh only 6 oz. The HHT11 single-button, direct-reading, non-contact digital tachometer has a speed range of 5 to 10,000 rpm and an optional contact tip for 5 to 20,000 inches per minute. The HHT11-R is a three-button, 30-function contact or non-contact digital tachometer, totalizer/counter, and stopwatch timer. It measures revolutions/minute and English and metric linear speeds. A remote optical sensor is available.