Measuring, signalling, monitoring, analyzing and controlling apparatus and instruments, namely, pressure sensors and pressure transmitters, humidity meters for measuring humidity of liquids, gases and solids, conductivity meters, instruments for measuring viscosity, Dk value, aridity, air volumes with bubble distribution, and protein content in liquids, gases and solids; level meters, namely, level meters that measure pressure of liquids, gases and solids; pressure meters, namely, pressure me...