The Densitek I Model MT-140 Beta Gauge is an online sensor for continuous monitoring of weight or density of web materials, such as textile fabrics, paper and wood paneling. A low-energy beta source transmits energy through the web material. The transmitted energy is received by a sensor that produces an electrical signal that is directly proportional to web density. The unit is available with two different beta sources for measurement ranges of 0 to 1,000 and 0 to 3,600 grams/sq meter. Accuracy is within 1 percent.