Replacement for Nutone Broan Grille : Through wall ventilation fans replace 97011790 S97011790 509S-A 509S-B 509SMG 503 505 507 509S (replacement old style) Thoughtful Design: Contemporary design enhances airflow through the fan grille while maintaining a sleek, low-profile look and is a perfect alternative to faded grilles for fresher air 97011790 Grille Excellent Quality: It is used for bathroom exhaust fan cover or kitchen ventilator fan, not easy to be affected by water vapor, not easy to fade and rust, not easy to be damaged, this upgraded version is made of metal threads, the knob threads and screws are reinforced, it is easy to fix in place Easy to Install: Remove the old grille, attach the new grille mounting bracket to the underside of the motor nut, screw the length of threaded rod into the grille knob appropriately, screw the knob into the grille mounting bracket, and secure the new grille in place, don't tighten it too much Daily Maintenance: Widely used in bathrooms, kitchens, rooms, etc. Regularly clean the fan blades and check whether the motor is functioning properly to avoid the accumulation of dust affecting the performance. FixIdea 97011790 Grille Wall Fans Part ,Exhaust Fan Cover for Kitchen Ceiling 509S-A 505-A