Melt-blown filter cartridges are made of polypropylene with the manufactural process: melting, spinning, drawing, receiving. Manufactural process lead pp fibers to interpenetrate and form winding path microporous structure.The fiber density along the direction of the filter diameter can be controlled, so the filter fiber density decreased from inside to outside. Features and Benefits                       ▶ All polypropylene construction ▶ Graded pore structure enhances dirt-holding capacity ▶ Unique proprietary process ▶ Easy and safe cartridge incineration and disposal ▶ No surfactants, binders, or adhesives ▶ Long service life and high dirt-holding capacity. ▶ Average pore size are widely optional ▶ Wide chemical compatibility