Wasps, Mud Daubers And Rodents Pose A Serious Threat To The Refrigerator On Your RV. They Can Enter Through The Vents And Cause Serious Damage By Building Nests That Interfere With Air Flow. Camco (Model RS 600) Flying Insect RV Refrigerator Screen Fits Dometic Refrigerator Vents Which Have 20 Inch Long Louver Openings. These Easy To Install Screens Will Help Ensure That Your Vents Stay Free From Costly Invasion By Unwanted Pests.