The 3M Filtrete 14 x 14 x 1 1000/1085 MPR Allergen Defense A/C Furnace Filter is a set of three pleated filters designed to last for up to 3 months each. With a MERV rating of 11, this synthetic filter is specifically designed to capture allergens and improve indoor air quality in both air conditioners and furnaces. The filter is white in color and ideal for maintaining a clean and healthy environment in your home.