Measuring, detecting and monitoring instruments, indicators and controllers, namely, gauges and sensors for measuring, testing and checking the temperature, pressure, quantity, composition and concentration of gasses and liquids; electrodes for sensors; cathodes; pH and oxidation reduction potential (ORP) sensors, [ conductivity sensors, optical sensors, ] electro-chemical sensors [ and gas sensors for measuring gas concentrations ]; diaphragms for scientific apparatus, namely, diaphragms for...