Whatman 25mm GD/X™ syringe filters are designed to enable easy filtration of samples larger than 10mL. They are available in a wide variety of filter media choices with a polypropylene housing and utilize the most advanced construction methods and design features available today. This level of engineering provides for the finest disposable filtration devices possible. Whatman 25mm GD/X syringe filters contain a unique prefiltration stack of Whatman Multigrade GMF150 (10:1¬µm) and Grade GF/F prefilters. Multigrade GMF 150 is a combination of two glass microfibre filters in one. Manufactured from 100% borosilicate glass, its construction consists of a coarse layer on top, meshed with a fine layer below. The Grade GF/F filter will retain fine particles down to 0.7¬µm. These pre-filters, when combined with the favorable apparent pressure generated within the device, allow you to filter even the most difficult samples with less hand force than ever before possible. Compared to an unprotected membrane, the volume of sample filtered can be three to seven times greater.