Unsurpassed for non-vacuum, high-speed filtration, these clear funnels have internal helicoid ribs to increase the filtration speed. Vertical outer ribs prevent airlock. Made from autoclavable plastic resin, the funnels are unaffected by corrosive liquids and are heat resistant to 177ºC (350ºF). Models 60-146440000 and 60-146480000 are molded with Topas® Cyclic Olefin Copolymer. Models 60-146400000, 60-146420000 and 60-146500000 are molded with TPX® Polymethylpentene.