BUILDMART - 18x18 Black Modern AC Vent Cover - Decorative Aluminum Air Vent - Standard Linear Slot Diffuser - Heating and Cooling Register Grille for Ceiling, Walls & Floors - Texas BuildmartThe Performance of This Buildmart Diffuser Was Verified Through Testing According to ASHRAE 70 and ANSI S12. 51 ISO 3741 Standard by AIRFLOW SCIENCES CORPORATION Submittals Available Upon Email Request Designed and Engineered to the Highest HVAC Industry Standards Commercial Grade Solid Aluminum with Modern Architectural Design This Model can be used in Ceilings, Walls, and Floors This Model can be used as a Supply Vent Cover and Return Vent Cover

30 x 12 30x12 12x30 12 x 30

ASIN: B09WV3BPKM

Entry size: 10" flex

Entry size: 9" flex in oval shape

Neck: 11 7/8" x 3 7/8" - Face: 13 15/16" x 5 15/16"

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

Neck: 35 3/8" x 1 5/8" - Face: 36 7/8" x 3 1/16"

14 x 10 14x10 10x14 10 x 14

Connects to: 6" flexible duct in oval shape

Ideal for Texas Buildmart 72" Lineal Slot Diffuser - 3 Slot

ASIN: B09J9ZM4NC

Mouth Dimensions: L: 35 3/4" W: 4 3/4"