Wasps, mud dauber nests, birds and rodents pose a serious threat to your RV water heater, furnace and stove. They can enter through vents and openings and cause serious damage by building nests that interfere with air flow. Protect your valuable investment by purchasing and installing Camco's Flying Insect Screens. These easy to install screens will help ensure that your vents stay free from costly invasion by unwanted pests.