the porous element at either end of a column that serves to contain the column packing. It is placed at the very ends of the column tubes or, more commonly, in the end-fitting. Frits are made from stainless steel or other inert metal or plastic, such as porous PEEK or polypropylene.
A filter element typically made of stainless, Hastelloy, Titanium, or polymers, usually 0.75 mm or 1 mm thick. Frits may provide better filtration than screens, but because they are thicker there is greater mixing potential, and they typically result in increased pressure drop.