Most common trap gear, used in freshwater fisheries in Poland, include fyke nets (żak, mieroża), kozak and (lake) przestaw. Trap gears can be divided into basic and combined ones. The latter ones consist mainly of żak and mieroża.

Żak is a trap gear with double-chamber fishing chamber shaped usually on five hoops. Both chambers have a gorge. First chamber is preceded by a narrow crown (koronka). Second one is ended with a cone-shaped kutel, from which, after loosening a string, fish can be taken out. Żaki can be single with one wing, double with two wings, or single with two wings. Size of żak is defined by the diameter of
the first hoop. During fishing żaki are set with the use of bottom poles embedded in the lake.

Mieroża has the same chambers as żak. The only difference is lack of a crown. Instead, they have a big annex. It is spread on a bow-shaped handle with a string as a bowstring. Construction of mieroża assures better adherence of the trap opening to the lake's bottom as compared with a żak. Ease of setting in overgrown parts of lakes is an advantage of a żak.

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