Filters are probably your single best source for keeping your system clean and your home free of contaminents. There are filters that are made from many materials. Some of them use spun fiberglass (least effective) polyester and blends that will capture more particulates. All filters use terms called arrestance, and MERV ratings. As a general rule the higher the number the better the filtering qualities will be. For permanent electrostatic filters, please see our separate section. All others will be noted here. Pleated Filters Fiberglass Filters Polyester Filters Pleated Equipment Filters OEM Electrostatic Air Filters Let us help you through the selection process. Value ac is a proud distributor of Hart and cooley registers, air diffusers, vent covers, and air conditioning vents. We can special order anything you need. Please call us at 1-888-242-7725 Toll Free for a quote. We want to earn your trust! Floor Registers and Vent Covers Blog