A pre-pleated filter that is ideal for clarifying suspensions and analyzing water and soil. Saves time with quadrant pleated circles for repeat or multiple analyses. Time saving with quadrant pleat circles for conical filter funnels for repeat or multiple analyses. Reduced overall filtration time due to the exposed additional surface; the normal slowdown in filtration speed due to particle loading is postponed. Maintained overall loading capacity as more filter area is available. Maintained flow rate due to the reduction of contact of the filter paper with the funnel side and the self-supporting shape of the filter itself. The pre-closing has no significant impact on the technical data and the same figures can be used for the flat circles. The maximum degree of fine dust filtration in the qualitative range. Capable of retaining the fine precipitates that occur during chemical analysis. Slow flow rate. Also available in flat form as Grade 5. GradeMeer tonenMinder tonen