Fits 8x10 Duct Opening Stamped Steel Return Air Grille Vent Cover Grille for Sidewall and Ceiling in White Surface Dimensions: 9.75" W X 11.75" H (8" W x 10" H Duct Opening)The Listed size 8"x10" is for inside duct opening measurement, actual outside dimension is 8. 75"x11. 75" Stamped Face Steel Construction with 1 2" fin spacing for high air flow applications. Screws are included for easy installation White Powder coating with matte finish Individually packed with cardboard box for ultra protection

This product has listed size 10“w X 8”h is for duct opening measurement only

The Listed size 10"x 3" is for inside duct opening measurement

actual outside dimension is 14'' X 14''

The distance between centers of holes is 11"

Durable Construction: This air supply register is made of sturdy stamped steel for long-lasting use and reliable performance

MATERIAL - PVC tubing

The listed size 6" x 6" is for the inside duct opening measurement

Duct opening – a hole that holds the duct neck to allow air to come out from HVAC system

Reliable Support: Enables secure installation of supply lines

Compliant with ANSI Z21

If your duct opening size is 12” x 12”

you will feel either too cold or too hot