Disposable Spinfilter P system is primarily used for medium perfusion in cell culture processes. To be effective, spinfilters must consistently retain living cells in the bioreactor while allowing the medium and product to be pumped through the filter membrane. The proper selection of spinfilter rotational speed and pore size prevent clogging of the filter membrane during operation. The disposable system requires no cleaning, and therefore no cleaning validation. The system is constructed from precision woven open-mesh PETP polyester fabric on a polycarbonate body. The material provides consistent surface properties for reproducible results. Standard pore sizes are 10-, 20- and 40 microns, with other pore sizes available by request. The disposable line is available for vessels ranging from 1 to 500 liters and can be used with a variety of stirrer shaft diameters.