593 is a standard grade filter papers for fine precipitates. Increased filter surface area increases total loading capacity and decreases overall filtration time. Reduced contact between filter and funnel maintains flow rate. Eliminated need to quadrant-fold filter circles to fit conical funnels saves time in repetitive or multiple analyses. Prepleated filters have the same technical properties as the respective filter circles. Cellulose filters are used in qualitative analytical techniques to determine and identify materials. Prepleated qualitative filters give improved flow rate and increased loading capacity compared to equivalent quadrant folded filters.