Filter assemblies; components and features thereof; and, methods of use and assembly

A filter cartridge comprising:

• (a) media having first and second ends;
• the media surrounding and defining a central open interior;
• (b) a first piece positioned at the first end of the media;
• (i) the first piece having a central air flow aperture arrangement therethrough;
• (c) a second, closed, end piece positioned at the second end of the media;
• and,
• (d) a housing seal arrangement positioned on the first end piece;
• the housing seal arrangement comprising:
• (i) a first, radially directed, seal surface defining a non-circular configuration, in extension around the central air flow aperture arrangement;
• (A) the non-circular configuration comprising at least three radially projecting sections, to define a plurality of spaced radially projecting lobes, separated by recesses, in the seal surface as the seal surface extends around the air flow aperture.