Is your GE microwave vent getting greasy? This is the exact replacement grease filter that goes on the BOTTOM of your microwave (models JVM1331WW01, WW02, WW03, or WW04). It catches grease and crumbs before they clog up the vent fan. You should clean it every month and replace it once a year to keep your microwave running well and avoid kitchen odors. Installation is easy—just slide it in and out. Check your manual if you need help. Make sure your model number matches before buying! Keep your kitchen air cleaner and your microwave lasting longer.