Toshniwal digital ultrasonic concrete tester [duct] is the latest innovative venture from toschcon jesco [ india] pvt ltd. It is a rugged, light and easy to operate instrument and uses a non-destructive technique for concrete testing. The technique includes the detection of velocity of ultrasonic pulses through the solid concrete block. The velocity of these pulses basically depends on the reinforcement density and elastic properties of the material used in the structure. The quality of concrete blocks is related to their elastic stiffness so that measurement of ultrasonic pulse velocity in such concrete blocks can often be used to indicate their elastic properties and quality . This instrument can be directly operated on 230 v ±15 percent , 50-60 hz or on 6v-10 ah battery. A four-digits seven-segment display or on 6v-10 ah battery. A four-digit seven-segment display indication is catered on the front panel. Accuracy of the instrument is ±0.1 microsecond for the entire range of 0.1 to 999.9 microseconds. For ease of operation hold control is provided, which displays the last reading. The instrument has the facility fof displaying waveform on the screen of an oscilloscope. Toshniwal duct finds its applications in determining the homogeneities of concrete, presence of voids, cracks or other imperfections, changes in the concrete which may occur with time or through the action of fire or chemical attack, comparison of the concrete structure strength with a known sample.