Slightly more retentive with a corresponding increase in filtration time (i. e. slightly slower filtration speed) and more absorbent than grade 1. In addition to general filtration in the 8 µm particle size range, the extra absorbency is utilised, for example, to hold soil nutrient in plant growth trials. Also used for monitoring specific contaminants in the atmosphere and in soil testing. Also available as folded filter (prepleated) grade 2V*.