BUILDMART - 6x4 MUD-IN Air Vent Cover - Drywall Mud-in White Air Vent - Mud Linear Slot Diffuser - Register Grille for Ceiling and Walls - Texas BuildmartOur Standard Linear Slot Diffusers have ASHRAE 70 and ANSI S12. 51 Engineering Certifications Designed and Engineered to the Highest HVAC Industry Standards Commercial Grade Solid Aluminum with Modern Architectural Design This Model can be used in Ceilings and Walls This Model can be used as a Supply Vent Cover and Return Vent Cover CFM: 104 ft3 min Effective Velocity: 9. 8 ft s Neck: 5 3 4" x 3 7 8" Face: 7 7 8" x 5 7 8" This is a Non Filter Model

Neck: 23 5/8" x 3 15/16" - Face: 25 1/2" x 5 7/8"

Neck: 19 5/8" x 19 1/2" - Face: 21 5/8" x 21 1/2"

30 x 18 30x18 18x30 18 x 30

ASIN: B0BRS6P2H7

Total Box Dimensions: L: 60 1/2" W: 4 9/16" H: 11 7/8"

Neck: 9 7/8" x 5 15/16"- Face: 11 11/16" x 7 5/8"

Here's a link to the Plenum Box that fits this Diffuser:

This Model can be used as a Supply Vent Cover and Return Vent Cover

60" X 1 3/4" Linear Slot Plenum Box - For Single Slot (1 Slot) Linear Diffuser - Texas Buildmart - Modern AC Vent Covers for Ceilings

Neck: 17 3/4" x 1 5/8" - Face: 19 1/8" x 3 1/16"

18" Linear Slot Diffuser - 3 Slot - Triple Slot Linear Diffuser - Texas Buildmart - Modern AC Vent Covers for Ceilings

ASIN: B09K5YJ9MS