Seitz-Swinney filter unit, that is used in microbiology. A very fine filter is placed between the two disks at the base and the wingnuts are tightened down to make a gas-tight seal. A solution is placed in the funnel, and compressed air is attached to the tube on top. The valve at the base of the funnel part is closed, and compressed air is used to force the solution through the filter. When the filter chamber is empty, the air is shut off, and more solution to be filtered added to the filter chamber. You continue until the filter is too clogged to continue or you run out of solution. This is done usually to cold-sterilize a media solution by passing it through a filter so fine that viruses are retained. Filters that fine will also retain water, requiring either vacuum or pressure to filter.
All Military surplus products are used, the condition of the products varies, and the quantities may be limited. Unfortunately, we can not accept backorders or returns on any surplus products.
Surplus condition scale:
Grade I Used in like new to excellent condition.
Grade II Used in good condition, may show minor use.
Grade III Used in fair condition, will show normal wear and tear from daily use.