A collapsible air cleaner filter is provided. The filter includes a pleated media filter having a first end, a second end, and a filter media extending between the first and second ends, wherein the filter media includes a first plurality of flexible end portions and a second plurality of flexible end portions, the first and second plurality of flexible end portions are separated by a plurality of pleats, and the filter media extends a first length between the first and second plurality of flexible end portions, and an end member coupled to the first end of the pleated media filter, the end member extending a second length parallel to the first length, the first length being greater than the second length.

An adjustable filter track system a filter track having a recess configured to receive a filter, and a frame having a first coupling feature configured to couple to the filter track in a first configuration and a second coupling feature configured to couple to the filter track in a second configuration, where the filter track and the frame are configured to hold the filter in place within the recess, and where the filter track is adjustable between the first configuration and the second configuration to accommodate different thicknesses of the filter.

An adjustable filter track system a filter track having a recess configured to receive a filter, and a frame having a first coupling feature configured to couple to the filter track in a first configuration and a second coupling feature configured to couple to the filter track in a second configuration, where the filter track and the frame are configured to hold the filter in place within the recess, and where the filter track is adjustable between the first configuration and the second configuration to accommodate different thicknesses of the filter.

A cleaning module for cleaning an air stream includes a hollow article which has an inlet port for the entry of the air stream to be cleaned and an outlet port for the exit of the cleaned air stream. A cleaning structure is provided for cleaning the air stream by particle separation and/or for filtration of the air stream. The cleaning structure has at least two separate cleaning sub-structures which through an opening element in the hollow article can be removed from the hollow article and/or can be arranged inside the hollow article.