18" Deluxe Base Board Return Air Diffuser. ( brown)

Code: RB40618G
Price: $46.88
Quantity in Basket: None
BASE BOARD RETURN AIR REGISTER:Deluxe 18" Baseboard Diffuser Register All-Steel Construction) (Brown)*************************************************************************************************************************************** Photo Shows 4-1/2" Height on all Models. Base Projection from wall 2-13/16" on all models. *************************************************************************************************************************************** * Frequently Asked Questions * What is "Free Area"? Free area is the total minimum area of the openings in the supply outlet or return inlet (usually in square inches) through which air can pass. Also known as the "see-through area". (See also "effective area"). What is "Effective Area" ? Effective area is the net area (in square feet) of a grille utilized by the area stream in passing through the face openings. It is used the the equation: CFM= Face Velocity X Effective Area. This is the basis for most engineering data. ***************************************************************************************************************************************