Nordic Pure Geothermal MERV 8 Plus Carbon odor control air filters are made with a 1 piece frame for strength and stability so no taping air condition filters together. The sturdy one piece frame and extra material makes it a high capacity HVAC replacement filter which really enhances it's performance. Our Geothermal Pleated Plus Carbon furnace filters are made to replace ClimateMaster Tranquility 20 model # TSV036, Tranquility 27 model # TTV038 and Tranquility 30 model # TEV038 filter # 76B0005N15. Our air filters work with your geothermal heat pump system to remove airborne particles and help eliminate odors in your home or office. It also removes levels of concentration of gases (VOC's) as well as particulates in the air while maintaining excellent air flow properties. These MERV plus activated carbon, odor reducing geothermal AC filters consist of a durable non-woven polyester MERV rated media infused with a naturally derived charcoal. All our pleated AC filters are manufactured using a heavy duty, moisture resistant beverage board frame. There is a metal mesh support grid bonded to the pleats for extra support. We recommend that you change your air filter every 30-90 days to maintain maximum efficiency. Almost ALL furnace filters have a different "actual size" than the nominal size printed on the air conditioner filter. It's best if you measure your air filter for the EXACT size and compare it to our "Actual Size" - and then you can be sure your A/C air filter fits!