58-E4800 is used to verify the quality of concrete. It allows the measurement of the transit time of an ultrasonic wave through concrete products such as beams, columns, walls, cubes, cylinders and other sample types and to determine the propagation time.

The instrument generates ultrasonic waves which are introduced into the concrete via a transmitter probe head held in contact with the surface of the concrete under examination. These waves are read by a receiver probe, held on the concrete face in the same way, generally on the opposite side of the concrete. The time taken for the wave to travel through the concrete from one probe to the other is displayed by the instrument.

Piezo-electric probe heads of high and low frequency are available. The first are used to increase the resolution so as to identify micro-fissures: the second are used to increase the useful distance between the two heads so as to examine concrete elements of considerable thickness.

An oscilloscope may be connected to the instrument so as to display the wave form and identify voids, cracks and other non homogeneous features in the concrete.