K&N doesn't list a filter for the ZX2, but the focus has several different filter listings. The Zetec filter for the ZX3 is 57-2526-2 and the SOHC 2.0 is HP-2009. the catalogue I used doesn't show the Application if you just enter the part # so, even though I know what the P# is; I don't know what the listed application is for the HP-2004.
