The Vevor 4-inch exterior wall vent cover is designed to improve airflow for dryers, bathrooms, kitchens, garages, basements, and similar ventilation areas. It features durable SUS304 stainless steel construction with a rainproof louvered flap for reliable outdoor performance. A built-in non-removable protective mesh helps reduce the entry of small animals and debris into the duct. The square design is compatible with flexible and rigid ducts, and pre-drilled holes support straightforward wall installation.