30"W X 16"H [Duct Opening] ALUMINUM RETURN GRILLE - Easy Air Flow - Linear Bar Grilles [Outer Dimensions: 31.875"W X 17.875"H] 18" Round Duct Pipe Design – These Supply Diffusers

Design – These Supply Diffusers with integral round necks are recommended for heating

For enhanced airflow control

especially in tight spaces where carrying tools is impractical

actual front end outer dimensions are 17

30"W X 16"H [Duct Opening] ALUMINUM RETURN GRILLE - Easy Air Flow - Linear Bar Grilles [Outer Dimensions: 31.875"W X 17.875"H] 18" Round Duct Pipe Design – These Supply Diffusers+ Product Details Size 30"w X 16"h is the size for the duct opening measurement only, actual front end outer dimensions are approximately 31. 875" width X 17. 875" height. High Quality High quality aluminum with counter sunk screw holes (screws included) and no sharp edges. Design Unrestricted airflow For Your HVAC system noise free components no vibrating louvers etc. Powder Coat Finish Smooth, shiny, scratch resistant, beautiful. Looks like it was