These autoclavable desiccators are made of polypropylene (PP) and polycarbonate (PC) and can hold a vacuum up to 740mm Hg for 24 hours without any greasing. Autoclavable at 121°C for 15 minutes. The top dome, molded in rigid and transparent PC, gives a crystal-clear view of the sample. The knurled knob on the top provides easy handling of the dome. The lower part is made of PP and includes a perforated PP desiccator plate. An internal groove on the flange holds the silicon rubber O-ring. The PP stopcock accepts 1/4" I.D. tubing and has a self-lubricating PTFE plug. Use the three-way plug to create a vacuum, release a vacuum, or for shut-off.