Depth filtration glass micro fiber. Fine porosity, fast flow rate, with a 1.6 micrometer size particle retention. Frequently used in the filtration of precipitated proteins and cells. Ideally suited for use as a filter for radioimmuno assay of weak beta emitters by scintillation counting and gravimetric determination of airborne particulate. Binderless borosilicate glass micro fiber. 55 grams per meter squared Basis weight. Depth filtration categorizes filter media that traps particulate within the random matrix of fibers found within the thickness of the media. The efficiency rating of the filter is characteristic of the complex pore structure that develops as the fibers overlap. The fibrous material within the filter is commonly glass micro fiber or polypropylene. In depth filters such as glass micro fiber, the purity of the filter is dictated by the presence of, if any, binder material that acts as a strengthening agent and aids in holding the fibers together. Because of the characteristically high flow rates of depth filters, they are generally used in applications such as single and multi-process removal of sediment and course particulate. Glass micro fiber filters are available without binders, making the inertmatrix an ideal medium to entra-sediment for further analysis and counting. Also, depth filtration media is commonly used as pre-filtration prior to surface filtration substrates such as membranes.