Filters for Geothermal furnaces by
30x36x2 MERV 11 Geothermal Air Filter 6-Pack
30x32x2 MERV 11 Geothermal Air Filter 6-Pack
28x30x2 MERV 11 Geothermal Air Filter 6-Pack
24x28x2 MERV 11 Geothermal Air Filter 6-Pack
28x30x1 MERV 11 Geothermal Air Filter 6-Pack