24" x 24" Drop Ceiling HVAC Return Grille - For T-Bar Lay-In - PERFORATED - INSULATED White actual front end outer dimensions 4 X 12 Is CRFG2028 Width_14in

actual front end outer dimensions are approximately 16 5/8" width X 26 5/8" height -

+ Product Details Size - 26"w X 18"h is the size for the duct opening measurement only

please note that the total outer dimensions of the grille measure 10" in diameter

Looks like it was just waxed

+ Product Details Size – 12"w X 10"h is the size for the duct opening measurement only

24" x 24" Drop Ceiling HVAC Return Grille For T Bar Lay In PERFORATED INSULATED White actual front end outer dimensions 4 X 12 Is CRFG2028 Width_14in actual front end outer dimensions are approximately 16 5 8" width X 26 5 8" height + Product Details Size 26"w X 18"h is the size for the duct opening measurement only