Each waste water tank requires an air breather line, through which unpleasant odours may escape. This can be prevented by installing a VETUS no-smell filter into the breather line. The no-smell filter element contains a special odour-absorbingmaterial. The filter can be installed very easily. Model NSF38 is suitable for Ø 38 mm breather hose. The filter element is exchangeable and should be renewed once a year.