Power-free, direct-read, GSM module,transceiver control circuit, SIM card, ... Q3=2500L/h or Q3=4000L/h optional,R=100,2% accuracy. In line with the relevant requirement ... . Reliability of date: Using the patent technology, the read electronic data is exactly actual display of digital, without ... by fixed quantity: According to the program, the system read and test the quantity used, and compare with the ...