Increase sample protection and filtration efficiency with Thermo Scientific Nalgene Rapid-Flow disposable Filter Units with PES Membrane. These units feature the exclusive Rapid-Flow support plate design, providing fast flow rates and high throughput. The last line of defense against cell culture contamination—low protein binding polyethersulfone (PES) membranes with low extractables are the best choice for sterile filtration of cell culture media, serum, additives and buffers.