Filters Fast Air is a popular air filter brand. It is a name you can trust if you want an economical alternative for quality air conditioner filter. When you want to determine the efficiency of a filter, you need to know the Minimum Efficiency Reporting Value or MERV. The higher the rating of MERV, the better is the efficiency of the filter. MERV 8 and MERV 11 ratings of Filters Fast Air Filters are both available. If you use a filter with low MERV rating, the air flow of your heating and cooling system will be affected.