Version 1.6 for the USM-2 Ultrasonic Bold Meter focuses on eliminating or reducing minor measurement fluctuations that might have previously occurred with the technology. Its result is greater measurement stability, repeatability and accuracy. It provides precise measurement of elongation and load in threaded fasteners. It is a compact, lightweight, field-portable unit for real-time bolt measurement on fasteners of virtually any metal material, from 1 in. to over 50 ft long. To operate, a small transducer is placed against the head or stud end of a fastener, which introduces an ultrasonic sound wave that travels the length of the bolt. When the sound wave returns, the microprocessor converts the transit time to a length using constants based on the bolt material.