10x4 Black Premium Aluminum Linear Slot Diffuser (Pack of 2) – Modern Design (Duct Opening) FL The outer frame measures 5

The outer frame measures 5

The slim neck is especially useful for shallow ceiling cavities where full-depth diffusers have limited room

choose a dedicated 6x4 air return grille with pre-filter instead

This is a replacement-first diffuser

You’re left choosing between a dated louvered grille or an expensive remodel

10x4 Black Premium Aluminum Linear Slot Diffuser (Pack of 2) – Modern Design (Duct Opening) FL The outer frame measures 5CHECK SIZE BEFORE PURCHASE: This 10x4 linear slot diffuser fits a 10" 4" duct opening (the hole in your wall, ceiling, or floor not your old cover face). See the full 10x4 sizing guide Fits a 10" 4" duct opening measure the hole, not your old cover face. 2 pack format ideal for matching paired vents or updating two rooms with one consistent finish. Drop in surface mount replacement no drywall, flooring, or duct modification required. Modern minimalist