Grade 4 filter circles and sheets
Grade 4: 20-25µm
Extremely fast filtering with excellent retention of coarse particles and gelatinous precipitates such as ferric hydroxide and aluminum hydroxide. Very useful as a rapid filter for routine clean-up of biological fluids or organic extracts during analysis. Used when high flow rates in air pollution monitoring are required and the collection of fine particles is not critical.
To help you choose the right filter for your application please click on the image below that will take you to the application guide for:
 There is also a link to the Cytiva Filter Paper Selector Guide