SMI Ventilation Products comes in a variety of sizes as well as 2 great designs-traditional (Victorian) & contemporary (Essex). customize your home with decorative cold air returns; no more dented metal vents, made from high strength polymer resin. Check out the variety of sizes and styles so that your home can be customized throughout. You no longer have to hide that cold air return vent behind furniture or spend a lot of cash to cover your HVAC openings. Grille trim screws required are included. To measure your grille requirements, measure the size of your HVAC opening and refer to measurements on this site to ensure your selection for decorative registers or grille is correct.