Allows the separation of coarse solids from samples with bacteriological germ detection in a single operation, before and during the actual germ-retaining filtration step.

It is used between the funnel and the lower part of the stainless steel vacuum filtration devices. 11301, a white cellulose nitrate (cellulose ester) membrane filter with a pore size of 8 ?m is used as a pre-filter. It retains coarse particles in the sample to be tested, which flows through the membrane filter to the test filter (e.B. 0.45 ?m) of the underlying filter support of the vacuum device. After filtration is complete, the test filter is incubated. The colonies can grow on the filter surface without being disturbed by or superimposed by an excess of particles. Autoclavable and flammable. simple separation of coarse particles is made of high-quality stainless steel sterilizable.