30931 Hunter Air Purifier Filters (Aftermarket) Hunter Replacement Filter Fits Hunter models 30212, 30213, 30240, 30241, 30251, 30378, 30379, 30381, and 30382. The sub-micron filter captures airborne particles as small as .1 microns from the air. Uses Electrostatically charged filter material! Last up to 6 months under continuous use. This is an aftermarket filter.