Filter Paper, round, Grade 42, 90 mm, 100 pc/PAK

Whatman Grade 42 is equivalent to Munktell 393 and Schleicher & Schuell 589/6
Properties: -Slow filter paper-Filtration speed of 1870 s/100ml-A world standard for critical gravimetric analysis with the finest particle retention of any Whatman filter paper. Typical analytical precipitates include barium sulfate, stannic acid and fine precipitated calcium carbonate.

You can find the certificate here if necessary: ​​https://www.cytivalifesciences.com/en/de/support/quality/certificates