{"product_id":"20x21x1-air-filter","title":"20x21x1 Aerostar Air Filter","description":"A nominal 20x21x1 return takes a filter at 19 7\/8\" x 20 7\/8\" x 3\/4\" actual. Odd-sized returns like this show up where the original equipment installer used a non-standard grille opening, which is common in custom builds and certain regional HVAC markets. This Aerostar is built to the actual spec without adjustment, so it'll seat properly without forcing or wedging the frame. MERV 8 covers standard household filtration for dust, lint, and pollen. MERV 11 steps up for pet households or homes with mild allergy concerns. MERV 13 captures fine particulates - smoke, bacteria, virus carriers, wildfire particulate - the grade for households with respiratory issues. Pleated synthetic media construction with an electrostatic charge built into the fibers. The pleats give you substantially more surface area than a flat fiberglass filter at the same nominal size, which is why this filter runs 60 to 90 days between changes under typical conditions. The electrostatic charge improves capture in the sub-micron range, where mechanical filtration alone reaches its physical limits. Manufactured in the USA by Con-Air Industries, Orlando, Florida. Cardboard frame, reinforced for shape retention. MERV 13 in this depth wants a 30-to-60-day change interval because higher filtration grades load up faster than MERV 8 or 11.","brand":"Aerostar","offers":[{"title":"MERV 8 \/ 6","offer_id":41902354530458,"sku":"P80S.012021-6","price":68.04,"currency_code":"USD","in_stock":true},{"title":"MERV 11 \/ 2","offer_id":41902354366618,"sku":"P15S.012021-2","price":42.84,"currency_code":"USD","in_stock":true},{"title":"MERV 13 \/ 2","offer_id":41902354399386,"sku":"P25S.012021-2","price":45.16,"currency_code":"USD","in_stock":true},{"title":"MERV 8 \/ 4","offer_id":41902354432154,"sku":"P80S.012021-4","price":54.64,"currency_code":"USD","in_stock":true},{"title":"MERV 11 \/ 4","offer_id":41902354464922,"sku":"P15S.012021-4","price":75.24,"currency_code":"USD","in_stock":true},{"title":"MERV 13 \/ 4","offer_id":41902354497690,"sku":"P25S.012021-4","price":83.16,"currency_code":"USD","in_stock":true},{"title":"MERV 8 \/ 2","offer_id":41902354333850,"sku":"P80S.012021-2","price":30.9,"currency_code":"USD","in_stock":true},{"title":"MERV 11 \/ 6","offer_id":41902354563226,"sku":"P15S.012021-6","price":110.22,"currency_code":"USD","in_stock":true},{"title":"MERV 13 \/ 6","offer_id":41902354595994,"sku":"P25S.012021-6","price":113.04,"currency_code":"USD","in_stock":true},{"title":"MERV 8 \/ 12","offer_id":41902354628762,"sku":"P80S.012021-12","price":121.08,"currency_code":"USD","in_stock":true},{"title":"MERV 11 \/ 12","offer_id":41902354661530,"sku":"P15S.012021-12","price":198.24,"currency_code":"USD","in_stock":true},{"title":"MERV 13 \/ 12","offer_id":41902354694298,"sku":"P25S.012021-12","price":203.16,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0591\/6937\/4362\/files\/20x21x1_MERV8_6pk.png?v=1787938748","url":"https:\/\/myairfiltersdeliveredeals.com\/products\/20x21x1-air-filter","provider":"Air Filters Delivered","version":"1.0","type":"link"}