Atlas Scientific EZO-EC Embedded Conductivity Circuit 0.07 &minus; 500,000+ &mu;S/cm Reads Conductivity, Total Dissolved Solids, Salinity, Specific Gravity (sea water only) = 1.00  1.300 Range: 0.07  500,000+ S/cm Accuray: +/  2% Data Protocal- UART & I2C Operation Voltage: 3.3V  5V