Strong filter with very fast flow rate. Ideal for coarse particles and gelatinous precipitates. Smooth surface. Time-saving Whatman qualitative grades are offered in this convenient form, which have major advantages over flat circles. Savings in time required to quadrant-fold circles to fit conical filter funnels in repetitive or multiple analysis. Decreased overall filtration time with extra surface area; normal slow down of filtration speed with loading of particulate is postponed. Increased total loading capacity because more filter area is available. Maintained flow rate because of reduction in filter paper contact with funnel side and the self-supporting shape of the filter. Prepleating does not significantly affect any technical data and the same may be used for flat circles. Retention: 25µm. 100/Pack. Whatman #: 1214-320.