Introduction The series of products are encoded and decoded by a computer algorithm based on encryption and decryption rules. The user inputs the 8-bit code that produced by the management system to realize the purchases recharge. On account of using a plain language input with no carrier, the user can go to the places designated by operating companies to buy code directly or get the code by phone. With 8-bit password, the users can recharge by themselves without considering time and space constraints, and it is simple and convenient to use. Operating units can manage hundreds of thousands of users with little manpower and equipment, and complete manage service fees and charges without leaving home, which puts an end to the phenomenon of the arrears. Range of application To measure the cold water that flows through water pipe and control of water fees. Main features: Multi-current Power-off memory function Sensitive/dependable function Dynamic display function The measurement accuracy reaches b degree of iso 4060b Prompting function General purpose Overdraw function Prepaid function Auto alarm function Auto control function Anti-water-larceny function Technical parameter: Gb/t778_1996 base meter operation criteria Current working volts: 3.00v li-ion Measuring precisionín0.01 m³ Pressure lossín0.1mpa pressure loss Max working pressure1.6mpa Quiescent currentín12ua Data holdí²8 years Temperature0íµí40íµ