Desiccators, Vacuum, Clear Base, 10" 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 120 degrees 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 transparent PC bottom provides increased viewing clarity. An internal groove on the flange holds the silicon rubber O-ring. The PP stopcock has a self-lubricating PTFE plug. The three-way plug opens to create a vacuum, closes to hold a vacuum, and opens again to release a vacuum.