Extremely strong. It has a high wet strength due to the addition of a small quantity of chemically stable resin. Normal qualitative applications will not introduce any significant impurities into the filtrate. The resins do however contain nitrogen so this grade should not be used in Kjeldahl estimations etc. This filter paper is only half the thickness of Grade 113 and is suitable for coarse or gelatinous precipitates. The smooth surface allows for easy recovery of precipitates. It has a fast flow rate. Retention: 25¬µm. 100 circles/box.