Whatman Reeve Angel Grade 201 is a general qualitative filter with relatively slow filtration speed. Retains medium-fine precipitates. Smooth surface and close texture. Widely used in industrial laboratories and students laboratories for routine filtration. The filter is wet-strengthened with a small amount of chemically stable resin to extend the life of the filter and improve handling. Normal qualitative applications will not introduce any significant impurities into the filtrate. However it is not recommended for Kjeldahl nitrogen analysis. 100/box.