DESCRIZIONE
The invention relates to a filter unit (1, 19) comprising: at least one spacer fabric (3) which comprises a first and a second cover layer (4; 5), each of which comprises a plurality of openings (6) that are delimited by edge regions (7). Threads (8) extend from the edge regions (7) of the first cover layer (4) to the edge regions (7) of the second cover layer (5), and the at least one spacer fabric is rolled, twisted, and/or compressed in at least one section.