Selecting the purification equipment according to the actual air consumption while Interlocking several compressors only use one set purification equipment. If there is a stand-by compressor, you can select the purification equipment only for the running compressor. Compressed air goes through the air receiver; the moisture content of the compressed air will be removed by the air dryer visa the Pre-Air filter. The particle diameter = 1um and oil content = 0.1ppm after the After-air filter. If you select the Final-air filter, the particle diameter = 0.1um and oil content = 0.01ppm.