PHS-1705 is a PH ORP meter with the most powerful functions and the most convenient operation on the market. In the aspects of the intelligence, the measuring property, the usage environment as well as the external structure, great improvement has been made, so the accuracy of the instruments is very high. It can be widely used for continuous monitoring of PH values of the solutions in thermal power plants, chemical fertilizer, alloy, environmental protection, pharmaceutical, biochemical, foodstuff, running water, etc.