The Bulb is an OEM part for Frigidaire microwaves. It provides interior lighting, allowing you to see inside the microwave during cooking and when the door is open. You should replace the bulb if it burns out or becomes damaged. Over time, the filament inside the bulb can wear out, or the bulb itself can break due to impacts or electrical issues. Symptoms of a bad bulb include: No interior light when the microwave is operating Flickering or dim light Visible damage to the bulb This OEM replacement is also compatible with Electrolux, Gibson, Kelvinator, and Kenmore models.5304461116 (AP4057355) replaces 5304464090, 1260965, AH1765541, EA1765541, PS1765541.