PH Combined（gel KCL）, pH Skin, Oxygen(DO), Pt/ORP, Conductivity electrode, etc Range: 0--14 pH, Temp.°C: 0--50°C, Reference electrode: Ag/AgCl, Potential: 7 +/- 1, or 2 +/- 1 pH, ORP: -150--1050mV, Conductive cell constant: 0.8--1.2 cm-2,