On which on? The m60s you just replace it (the filters look like toilet paper rolls) and just dry the desiccant on the speedair . The purple is the tsunami,the 2 in the middle is the m60s and the speedair desiccant is on the end. That's basically one water separator and 3 dryers before entering the shoebox.i will add a good micron filter after the desiccant filter to catch any dust also before entering shoebox compressor.