Used commonly in quantitative and qualitative analysis, filter papers must be closely matched to the application according to the physical characteristics of the filter paper. There are many sizes, materials, types, and grades of filter paper available for a variety of applications. Whatman® filter papers use only the highest quality raw materials for high reproducibility and high uniformity. Whatman® cellulose filter papers are manufactured from high-quality cotton liners that are treated to achieve an α-cellulose content >98%. A wide selection of Whatman® filter papers are available to suit numerous laboratory applications. Pre-pleated (folded) filter paper is also available for convenience.