The top-of-the-line Return Air Grille is bar-type. And the best bar-type Return Air Grille is made of aluminum. Light weight, rust resistant, and durable; Truaires A270 Return Air Grille and A290 Return Air Filter Grille is the best of the best for residential return air applications. Each aluminum fixed blade is set at 45 degrees and ¾ apart. Finished in our pristine white powder-coat, this is a tough act to follow!