TDS 100HS is a portable, handheld, clamp-on ultrasonic flow tester used for non-invasive, unobstructed, unwetted, highly accurate measurements of the flow velocity of liquids in metal, plastic and rubber pipes and tubes with a diameter of 20 ... 100 mm / approx. 3/4 ... 4". Ideal for use in oil and gas, water and wastewater, chemical, food and beverage, pharmaceutical, metals and mining, pulp and paper, power and heating, ventilation, air conditioning and refrigeration (HVACR) industries, this ultrasonic flow tester features user-friendly velcro-strap clamps that allow for quick and easy repositioning of the electroacoustic transducers.