Amprobe TACH20 Digital Tachometer

Features include; Display of rotational speed, display of surface speed in m/min, ft/min and in/min. Display of length measurement in m, ft and inch. Display shows last, maximum or minimum value. Optical (non-contact) or mechanical, adapter based measurement. Visible optical measurement via an infra-red beam. Auto power off after 30 seconds (data remains stored in memory).