Whatman Grade No. 42 Quantitative Filter Paper Ashless Whatman. 42 Quantitative Filter Paper Ashless 1442-090 is ideally suited for the pre-filtration and trapping of coarse particulates. In particular Ashless Whatman No. 42 Quantitative Filter Paper is most suited to the separation of coarse particulates. Whatman Grade No. 42 Quantitative Ashless Filter Paper is highly recommended for the pre-filtration and trapping of coarse particulates. For example coal tar dyes certain pharmaceuticals leaded gasoline certain uraemic metals certain pharmaceutical intermediates etc. When the paper shows needle indications of filtration through coarse material such as sand it is time to change the filter. Likewise all chromatography checks are to be performed on ashless paper. Specifications for Whatman Grade No. 42 Quantitative Filter Paper Ashless Whatman 1442-090 : Diameter cm: 9.0 Whatman No.: 1442-090 Unit: Pack of 100 Porosity: Fine Flow Rate: Slow Particle Retention: 2.5 m (Please note that the description and stock photo may not correspond to the specific model listed above) We offer only genuine Whatman products authorized for sale in the U.S. and other markets so you can be sure that you are buying authentic Filters with a full manufacturer's warranty in addition to our own 100percent Satisfaction Guarantee. We are your premier online distributor for Whatman Filters. We are an authorized supplier to all federal and state government agencies as well as to research and educational institutions and can facilitate volume orders on many types of laboratory equipment lab consumables and other products to help fulfill your specific needs. We offer Free Shipping and FREE USPS shipping to APO and FPO addresses on all orders in our store over 49. Please refer to our APO/FPO Shipping and Export Restrictions for more information on export to APO/FPO addresses. In addition to the Whatman Grade No. 42 Quantitative Filter Paper Ashless Whatman 1442-090/ 28480-081 we carry a full complement of Filters as well as other product offerings from Whatman. We also carry a full line of Whatman accessories to help meet your laboratory and scientific needs. For a complete selection of Whatman Filters please visit our Whatman page. For more brand name Filters please visit our Filters store section. To see our complete line of lab medical industrial and scientific products please see our science and lab equipment online catalog. Whatman Grade No. 42 Quantitative Filter Paper Ashless Whatman 1442-090