21531200 100935 M132439 Pre-Filter Fits Ariens Mower ModelsOne New Aftermarket Replacement Foam Pre Filter for Ariens, Fits John Deere, and Fits Grasshopper Mowers This aftermarket foam pre filter fits over the primary air filter element on Kohler CH and CV series small engines to trap larger particles before they reach the main filter, extending air filter life and protecting engine internals. It is a direct foam pre cleaner replacement compatible with Ariens mowers, Fits John Deere (Fits JD) ZTrak and lawn