The HRI electrode is an industrial ORP electrode designed to measureORP levels in water and waste. The unique design of the electrode enables measuring in hard environmental solutions, eliminating the interferences of heavy metals in the sample. The electrode is using a double junction reference and a 3 M KCL solution combined with Silica to ensure a positive high pressure between both junctions. The wet junction is made of a ceramic ring that ensures a big wet surface with a large area of measurement. The gold disc used for the measurement eliminates heavy metals interferences.