This White 18" x 18" Shoemaker 901 Series Vent Cover is designed to fit and cover an 18" wide by 18" high opening. Shoemaker has a complete line of products designed for homes, offices, stores, and many other commercial applications. The quality and simplicity of this airfoil blade single deflection diffuser are only two of the many reasons why Shoemaker Manufacturing leads the field in innovative air-grille design for real world applications. The Shoemaker 901 Series Aluminum Airfoil Blade Single Deflection Diffuser creates a 2-way air flow in a single plane. Its airfoil blades have nylon bushings for easy adjustment and quiet settings. The adjustable louvers on this particular air-grille run parallel to the longest dimension. Its aluminum frame is extruded with signature line marks. Normally, vent covers are mounted in walls but this diffuser can be mounted in ceilings as well. The standard color of this grille is soft white but it is also available in driftwood tan. Optional designer colors, satin anodized aluminum and plain mill finishes are also available. The Shoemaker 901 Series Aluminum Airfoil Blade Single Deflection can be ordered with "F" Torx center pin tamper-proof screws for added security. Be sure to measure the hole opening size instead of measuring the face plate of your old grille. This grille is designed to fit over an 18" x 18" existing hole or duct. Refer to the Specification Sheet for more information.