JCJ Enterprises is a trusted brand that designed the Mud Dauber Screen to help you protect your RV furnace or fan, making camping adventures less trouble-free and more enjoyable. The Mud Dauber is a metal protective screen to keep mud daubers, wasps, mice, birds, and other creatures out of conduits such as furnace vents, fan vents, water heat vents, stove vents, and refrigerator vents. JCJ products are made in the USA and guaranteed to have no defects in material and workmanship.