These Edwards ITF20K ITF-20-K dust element prevents the entry of dust particles in the pump. The impedance of a clean filter reduces the pumping speed of a 20 m3h-1 pump by about 20% at 1 mbar and 25% at 10 mbar. Filter efficiency better than 96% (tested to BS2831, dust number 2). For complete specifications download the instruction manual (see below avaliable downloads).