The 25mm vacuum microfiltration assemblies are designed to handle small volumes of liquids for analysis of particulate or microbiological contamination. The funnel is graduated from 5 to 15mL in 1mL increments. Prefilter size is 16mm diameter and the approximate filter area is 2.5cm. Connection to 125mL filtration flask (available as an accessory) is made with a No. 5 silicone stopper. with Stainless Steel Support Used for filtering viscous or proteinaceous solutions or to produce ultra clean filtrate. This unit is supplied with a 316 stainless steel support screen, PTFE support screen gasket, glass support base, 15mL graduated funnel, anodized aluminum clamp and a #5 silicone stopper.