Using this rangehood filter material is easy. First, measure the size of your rangehood filter and then use scissors to cut the material to the right size. Place the white side facing the direction where the grease comes from so it can trap the grease effectively, and the black carbon - impregnated side will take care of the odors. When it comes to maintenance, check the filter regularly. If you notice that the white side is full of grease or the filter doesn't seem to be getting rid of odors as well as before, it's time to replace it. Keep the filter in a dry place when not in use. Remember, this item is now supplied in plain packaging, so don't be surprised when you receive it. And since we have 25 years of experience in supplying appliance parts, you can trust the quality of this product.