[Class : 7] Decanters For Waste Water Purification Installations For Sewage, And Parts Therefor; Pumps And Valves (Parts Of Machines) For Sewage Purification Installations; Apparatus For Introducing Oxygen Into Sewage Purification Installations, And Parts Therefor.[Class : 9] Instruments For The Quantitative Measuring Of Sewage Treatment Process Parameters, Including Oxygen ...