14" x 14" [Duct Opening] Ceiling Supply Diffuser Vent Cover – 2-Way Airflow with Full Aluminum Frame, Back Blades & Opposing Blade Lever Damper [Outer Size: 17" x 17"] 2-Way + Product Details Size -

+ Product Details Size - 28"w X 18"h is the size for the duct opening measurement only

Design – This duct fitting is designed for transitioning oval wall stack ducting to round sheet metal pipe

+ Product Details Size – 24" x 36" or 36" x 24" is the size for the duct opening measurement only

actual front end outer dimensions are approximately 27 5/8" width X 14 5/8" height

+ Product Details Compatible replacement for WC‑15 series speed controllers

14" x 14" [Duct Opening] Ceiling Supply Diffuser Vent Cover – 2-Way Airflow with Full Aluminum Frame, Back Blades & Opposing Blade Lever Damper [Outer Size: 17" x 17"] 2-Way + Product Details Size -+ Product Details Size Refers to duct opening only. The face frame extends roughly 1. 5" on each side. Do not measure the overall grille for sizing. Design All aluminum frame and back blades. Rustproof and built to last in moisture prone environments. Quiet Airflow Opposing blade damper design reduces vibration and noise for smoother air distribution. Clean Finish White powder coated surface resists chips, scratches, and discoloration over time. Easy