Skip a trip to the store and buy the 22" x 18" Steel Blade Grille with 45° Fixed Blades Parallel to Long Dimension in soft white (Shoemaker 935-22X18) from PlumbersStock.com. The 935 series offers steel blades are spaced at 2/3-inches and fixed at 45 degrees. Take note that the blades run parallel to the longest dimension. There is no damper. If you want that, then you need the 935-O series. Countersunk mounting holes provide a flush appearance. Shoemaker designs HVAC solutions that are both affordable and practical.