This 100Pcs or Set fast speed quantitative filter paper are used when you are generally concerned about what is left on the filter. Quantitative filters are used for gravimetric analysis or filtration where the precipitate is to be recovered, which is also concerned about the quantity of substance that remains on the filter Specification: Material:Cotton Fiber Filter Type:Quantitative Filter Filter Speed:Fast Speed (<35s) Max. Aperture Diameter:20to25um Ash Content: ¨¹0.01 percent Quantitative Filter Area:80 ¨¤4g or m2 Quantity:100Pcs or Set Size:(Filter Diameter) 1: 7cm 2: 9cm 3: 11cm 4: 12.5cm 5: 15cm 6: 18cm Feature: 1. 100Pcs or Set quantitative filter paper, fast speed 2. With numerous small holes on its surface made from cotton fiber, it only allows liquid particles to pass through while solid materials with large volume Note: 3. Light weight, convenient to use and carry, accurate testing 4. It requires less filtration time than filter paper with medium and slow speed 5. It covers a wide range of laboratory applications, which is frequently used for clarifying liquids 6. It is widely used for gravimetric analysis or filtration where the precipitate is to be recovered 7. It is suitable for precise quantitative analysis since there is little remaining ash which has little effect on the analysis results. The amount of ash produced after ashing does not exceed 0.0009 percent Note: You are supposed to make a distinction between quantitative filter paper and qualitative filter paper and choose the proper one according to your requirement 1. The quantitative filter paper is used for gravimetric analysis or filtration where the precipitate is to be recovered, for example from a Buchner funnel filtration under vacuum The amount of ash produced after ashing does not exceed 0.0009 percent 2. The qualitative filter paper is used for qualitative techniques to identify materials. They do not offer the same level of precipitate recovery as quantitative filter paper The amount of ash produced after ashing does not exceed 0.13 percent Package Include: 1x100Pcs or Set Quantitative Filter Paper