Handheld vacuum gauges THERMOVAC TM enable an easy pressure measurement. The sensors of the TM 90 series work after the Pirani principle. The TM 101 combines high-quality sensor technology with modern process technolog in a handy design. By combinig a piezo-resistive pressure sensor for the upper and a Pirani for the lower pressure range, the measureurments mad by the THERMOVAC TM are independent of the type of gas above pressures of 15 mbar (11.25 Torr). Especially noteworthy is the exceptionally long battery life.