5 layers of aluminized grease ensures better filtration and helps your range hood maintain its performance. Hood filter fits most leading of range hoods/range hood vents. Remove the old range hood filter, find the interface of the clean filter, and install it after confirming that the interface is consistent. To maintain the best performance of the cooker hood, please keep the air circulation and remove the odor. It is recommended to replace the metal oil filter of the range hood every 3-6 months.