This filter holder is available in two versions differing from each other only in the type of the filter support. The filter with glass frit
ensures uniform distribution of retained particles and is therefore recommended, when the residue on the filter surface is of interest. The device with PTFE-coated screen support, on the other hand, is due to its ease of clean more preferable, when the filtrate is required or when liquids difficult to remove from glass frits have to be examined.
The PTFE ring which holds the glass frit and the screen support allows autoclaving the devices with a filter in position, and protects the edge of the glass frit from breakage and potential leakage. It has a rim around the upper edge to simplify the positioning of the membrane filter when inserted and a silicone O-ring in the underside for leak-proof seal on the filtrate side.

All areas, where liquid and device can get directly in contact, are made of glass or PTFE. The device, in combination with solvent-resistant, hydrophilic RC-membranes, is therefore ideal for ultracleaning and degassing solvents and solvent mixtures for HPLC, GC and AA. Convenience of handling is ensured by several beneficial features. A 6 mm wide non-ground rim above the ground glass neck of the suction flask prevents the filtrate from contacting grease on the ground glass surface and so avoids it becoming contaminated while being poured out of the flask. The hose nipple connector is made of polypropylene for safe connection of vacuum hose. The filtrate outlet spout ends well below the entrance to this hose nipple.