8" x 4" Adjustable Blade Sidewall Ceiling Register Vent Cover Diffuser Heavy Duty Stamped Steel (Listed Size is Duct Opening Inside Measurement)

Adjustable Air Register – Diffuser for sidewall or ceiling applications. The listed size 8“ X 4” is for duct opening measurement only, Actual outsize overall dimensions is 10“ wide (length) by 6” high(width). Size Selection Guide: Measure the size of the air duct opening(the size of the “hole” ). Select the listed size that match the duct opening size. The outside or overall size is 2” larger for both length and width so it can cover the “hole”. Do not use outside measurement for size selection.