... back light 3.Temperature compensation 4. Drinking water,Swimming pool and Tap water PH controller/PH meter/PH electrode ... carving process, electroplating wastewater, printing and dyeing, electronic semiconductor, chemical, pharmaceutical, etcFeatures:1.High impedance preamplifier, strong ability of ... 125mm13.N.W: 1 KG Drinking water,Swimming pool and Tap water PH controller/PH meter/PH electrode