The best way of using your cooker hood is to extract outside with a ducting kit, but if you cannot do this then using a charcoal filter & recirculating the air will be a perfect way to use your cooker hood. The Smeg Charcoal Filter KITFC152 protects the kitchen both from cooking grease & odours, keeping the air clean & healthy. The Smeg Charcoal Filter KITFC152 attaches to the motor inside your cooker hood to help remove kitchen smells & provide clean & fresh air.