Crown Vent Electrostatic Filter Media fits perfectly into our Size 12 Magnetic Vent Cover and filters out allergy causing particles 3-10 microns in size using static electricity:
 
MERV 7 Rating 
Filters pollen
Filters textile fibers
Filters dust mites
Filters mold spores 
 
Testing method with reference: GB/T14295-2019 & ASHRAE 52.2-2012