Camco Fur 200 Flying Insect Screen, designed for Duro-Therm, Suburban, & Durotherm. It effectively protects your RV water heater, furnace, and stove from wasps, mud dauber nests, birds, and rodents. These pests can enter through vents and openings, causing serious damage by building nests that interfere with air flow. Easy to install, these screens ensure that your vents remain free from costly invasion by unwanted pests. Comes with 1-year limited warranty.