The qualitative filter papers are manufactured from pure cellulose with a proportion of alpha-cellulose of almost 100 %. The ash content is about 0.06 %.

Grade 2015, medium to slow filtering, particle retention 5-8 µm, filtration speed 50 s according to DIN 53137, basis weight 87 g/m², thickness 0.16 mm

For fast filtration with fine particles, when the filtration speed plays a minor role.