The patented 2-stage filtering system adsorbs the residual amount of contaminants, without any need of complicated formula to dimension the unit. Such system, thanks to an electronic indicator, advises the operator when the filter element must be replaced. It is suitable for every type of drain: manual, electronic and timed. The oil is kept in the separator, and only the depurated water is let out. There is no need to dispose of the oil, but only of the filtering elements. It is suitable for every type of oil and emulsion, whereas for poly-glycol oil, contact our Technical Department.