Valterra's A10-1310VP Bug Screen for RV Refrigerator Vents are designed to fit Norcold refrigerator vents with 19. 75" louver openings. They are easy to install and offer minimal airflow restriction while ensuring that your vents stay free from costly invasion by unwanted pests (nesting insects, birds, and rodents). Screens should be inspected monthly and cleaned when necessary to maintain proper air flow. Screen measures 1. 3" x 19. 6".