The GVS polysulfone 47 mm autoclavable filter holder combines a number of key features and benefits, making it a tremendous value. To begin with, the funnel has only two pieces. There are no clamps or locking devices to manipulate. A unique gravity sealing design allows for one-handed operation with no danger of filter by-pass or sample leakage when using depth filters. And it is stable and very solid with no costly replacement parts. It all adds up to the easiest and most cost-efficient analytical funnel available. GVS analytical funnels are available in polysulfone for aqueous samples. The polysulfone unit is autoclavable and chemically resistant for cell culture and microbiological applications. There are graduations up to 350 mL with 50 mL intervals. The No. 8 stopper mounts in a standard 1-liter filtering flask for individual tests or in three- and sixplace stainless steel manifolds for multiple tests to run concurrently.