Location: The Charcoal Filter is located at the top of the microwave behind the grill vent. This is the only location where this filter fits. Models: This charcoal filter is specifically for the following microwave model numbers: PVM9179EK6ES, PVM9179EKES, PVM9179FL5DS, PVM9179FL6DS. Air Freshener: If the air from the exhaust fan does not smell fresh, this filter helps to reduce foul odors. Filters are normally replaced every 9 months depending on use. Installation Instructions: The original user manual for your microwave contains detailed instructions on replacing the charcoal filter. Use scenarios - After frying or cooking with strong aromas, install to reduce odors and keep kitchen air fresher. - In open plan kitchens or areas where odors travel to living spaces, use to maintain a neutral air environment. - In high usage or busy households, replace about every 9 months or as needed to maintain performance.