Thermo Scientific Orion® Nitrate Electrode 1.0 to 7 to 10-6 M. A separate reference electrode is unnecessary with this electrode, making it convenient to use with small sample volumes. Free flowing sure flow junction assures stable, drift free potentials. When measuring dirty samples that would clog conventional electrode junctions, the sure-flow junction can be cleaned by pressing the electrode cap. Cable length: 1m. Body diameter: 12mm. Cap diameter: 16mm. Measurement range: 1.0 to 7 to 10-6 M/14000 to 0.1 ppm as N. Temperature range: 0 to 40°C. Per each. Thermo Scientific Orion® #: 9707BNWP.