The Helios Fans RVK 315 is a durable and efficient louvre cover designed for sealing both air intake and exhaust openings. It is perfectly suited for systems using reversible fans, providing automatic operation via a built-in spring mechanism that ensures tight closure when not in use. Made from UV-resistant, impact-resistant polymer in a light grey finish, it offers robust performance in various environmental conditions. The stainless steel spring ensures corrosion-free longevity. Designed for easy installation and dependable airflow control, the RVK 315 helps maintain ventilation efficiency while preventing unwanted drafts or airflow when the fan is off.