Return Air Filter Grille Fits W30 x H20 In Duct Opening Air Grille with Filter Return Air Filter Grille How to Measure Efficient Air Exchange Easy to Replace and Maintain Easy Installation Multiple Size Options Installation Opening Dimensions: 29.7 x 19.9 in / 75.5 x 50.5 cm,Installation Opening Thickness: 1.06 in / 2.7 cm,Filter Slot Dimensions: 29.6 x 19.8 x 1.3 in / 75.3 x 50.3 x 3.2 cm,Item Model Number: 1RAF3020F-1,Product Dimensions: 32.7 x 22.5 x 1.6 in / 83 x 57.2 x 4 cm,Net Weight: 8.93 lbs / 4.05 kg,Filter Rating: MERV8