These filter papers for suitable for special applications.

Grade 11: Plain, hardened.
Grade 389F: Plain, for determination of fat in foodstuffs.

Grade 480: Plain, phase separation paper, hydrophobic silicone-impregnated paper.

Grade 918: Black filter paper, stained with a sulfur colouring to reveal the particles of bright colour, detection of fluorine or silicon and mycelium in cultivated mushrooms.

Grade 470: Plain, kieselguhr (diatomite) paper for fine turbidity.

Grade 69/K: Plain, activated carbon, used in laboratory: clarification and brightening of dull and dark urines, for polarimetric sugar determination and industry: filtration of galvanic baths and clarification of colored liquids.