The pre-filters are used for panel filters when they are exploited under conditions of air high dust level or when longer exploitation period is required.

For pre-filters production there is applied synthetic non-woven material that represents additional filtering partitions, which serve for air prior cleaning.

Pre-filters trap more large contamination fractions, owing to this they do not chock main filter.

Usage of air filters with pre-filters allows to reach sufficient increasing of filtering element absorbing capacity without noticeable increasing of resistance to air passing.