Whatman Grade No. 1 Filter Paper Whatman. 1 Filter Paper. Strainer paper is used primarily for the pre-concentration of granular and colloidal materials. Whatman Grade No. 1 Filter Paper Strainers classify the collected matter according to a pre-set porosity or degree of retention allowing no liquid or solid material to pass without retention. The paper is ideal where fast coarse filtration such as that required for the pre-concentration of colloidal particles or coarse suspended matter is highly resistant to chemicals and provides an effective reusable water filter. Order grade no. 1 Whatman strainers online today Specifications for Whatman Grade No. 1 Filter Paper Whatman 1001-090 : Size cm: 9.0 dia. Whatman No.: 1001-090 Unit: Pack of 100 Porosity: Medium Flow Rate: Medium Particle Retention: 11 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. 1 Filter Paper Whatman 1001-090/ 28450-081 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. 1 Filter Paper Whatman 1001-090