Nordic Pure 18x24x4M10+C-1 MERV 10 Plus Carbon AC Furnace Air Filters, Qty 1 Actual Size of Carbon Air Filter: 17 3/8 x 23 3/8 x 3 3/4 Odor absorbing activated carbon One convenient air filter - MERV 10 pleated plus activated carbon A simple solution for controlling both odors and dust particles Nordic Pure Manufacturer Direct since 1960 - Made in the USA