Filtrete 20-in W x 25-in L x 1-in MERV 14 2500 Smart Premium Allergen and Ultrafine Particle Electrostatic Pleated Air Filter in the Air Filters department at Lowes.com
Amazon.com: 20x25x1 (19.6 x 24.6) Filtrete 1250 Ultra Allergen Filter by 3M (4 Pack) : Tools & Home Improvement