Replacement filter set for Harbor Freight generator 4000/3200W with 6.5 HP horizontal shaft engine. It is shipped un-oiled; add a couple drops of oil to the filter and squeeze/work it for a minute in the supplied bag, then install. This is a complete filter set consisting of 2 filters. The first is a small pore foam filter, meant to trap dust; this installs closest to the carburetor. The second is a large pore filter, meant to catch larger items like sawdust and hair, and installs next to the first. Both should be oiled. Having an air filter in place is *critical* to the proper running of the engine. Fits the following generators: P/n 69729, 65414, 67560, 68528, 69676 Satisfaction guaranteed; buy with confidence