40" x 16" Aluminum Spiral Duct Air Vent Grille Cover - Fully Adjustable Double Deflection HVAC Air Supply [Outer Dimensions: 42w X 18"h] Filter Grille + Product Details Size -

+ Product Details Size - 4"w X 24"h is the size for the duct opening measurement only

+ Product Details Size - 24"w X 6"h is the size for the duct opening measurement only

Lock and Key included

complete with a set of sponge gasket and mounting frame

40" x 16" Aluminum Spiral Duct Air Vent Grille Cover - Fully Adjustable Double Deflection HVAC Air Supply [Outer Dimensions: 42w X 18"h] Filter Grille + Product Details Size -40"w X 16"h Is The Size For The Duct Opening Measurement Only, Actual Front End Outer Dimensions Are 42" Width X 18" Height SEE IN DESCRIPTION HOW TO MEASURE A GRILLE Installs Directly On Round & Oval Spiral Duct No Frames, Box or Other Attachments Needed Commercial Grade Aluminum Will Never Rust Designed for Warehouses, Factories, Workshops, Gymnasiums & Restaurants Easy Unrestricted Air Flow For Your HVAC System 180 Degrees Double Direction