Honeywell 50000293-002 Post Filter
Honeywell's best electronic air cleaners are now even better thanks to Honeywell's new High Efficiency Postfilter.  These new postfilters-featuring patented filtration technology-incorporate an electrostatic-charged open channel design that improves filtration efficiency with minimal resistance to air flow.  So homeowners can breathe easier knowing they're making the air in their homes cleaner without placing significant strain on their central air systems.PostFilter is intended for 16X25in F300 and F50F electronic air cleaners.  (Comes in 2-pack of filters measuring 16x12.5in each)