Bel-Art Polyethylene Buchner Table-Top Funnel with Medium Porosity Fixed Plate; 10.25 in. I.D, 8 in. Height (H14625-3510) Rugged and rigid polyethylene construction, ideal for heavy use 5" Rim to plate Fixed or removable porous filter plate supported by a multiple ring grid Filter plates are made of high density polyethylene, 6.4mm thick, with a non-porous ring at the periphery of the plate which seals filter paper when used Medium porosity plate is 45-90 microns; use from -80C (-112F) to 52C (125F)