Why are there two air filter slots in my HVAC system?

The FilterLOCK covers and seals the standard 1” furnace filter slots The overlapping two-piece design allows for filter slots measuring up to 25” in width

cover and engaging with said filling aperture , an air vented nozzle on said filter tube arranged within said perforated cas- ing and an

air ambulance lottery winners I have a house where the furnace has a 25 x 1 wide slot in the air intake where I slide the 16x25x1 filter in from the top

airbet88 slot login The HVAC contractor argued and said that a filter cover was not required at this location and it would not hurt anything to leave it open He