Kenmore CF-3 Upright Vacuum...
$6.99
Product details
Part 912 is a two-pack of CF-3 foam filters for Kenmore uprights - the filter that sits under the bag rather than in the door.
Its job is to catch whatever gets past the bag before air reaches the motor, which means it takes the worst of any bag that has split or been fitted badly. Ignore it long enough and the foam goes solid grey, airflow through the machine drops, and the motor runs hot for less pickup than before.
Wash it in warm water, press the water out and let it dry fully before refitting; a damp foam filter breeds a smell that then comes out of the exhaust every time you clean. Replace it when the foam stays compressed, discolours through, or starts to crumble at the edges. Having the spare means the machine is never out of service while one dries.