18" X 12" Steel Return Air Filter Grille for 1" Filter - Removable Frame - [Outer Dimensions: 20 5/8" X 14 5/8"] Copper Coil-Insulated Line Set High Quality – Polished pre-finish 4 X 12 Is CRFG2028 Width_14in

High Quality – Polished pre-finish gloss varnish ready to install - can also be sanded and re-finished according to application needs

+ Product Details Size – 20"w X 14"h is the size for the duct opening measurement only

Operating temperature from -40°f to +248°f [-40°c to +120°c]

+ Product Details Size - 20"w X 20"h is the size for the duct opening measurement only

All of these grills have dampers

18" X 12" Steel Return Air Filter Grille for 1" Filter Removable Frame [Outer Dimensions: 20 5 8" X 14 5 8"] Copper Coil Insulated Line Set High Quality – Polished pre finish 4 X 12 Is CRFG2028 Width_14in High Quality – Polished pre finish gloss varnish ready to install can also be sanded and re finished according to application needs + Product Details Size – 20"w X 14"h is the size for the duct opening measurement only