Our package includes 2 non-power roof ventilators, each with a hoop. The vent connection size measures approximately 4.33 inches (11 cm) in diameter and 7.48 inches (19 cm) in height. It ensures quick and efficient release of hot air from the roof space within minutes while protecting against rain and moisture. The non-power roof ventilator is constructed from high-quality 201 stainless steel, ensuring durability and long-term performance. The material resists rust and withstands high temperatures, making it suitable for various weather conditions. This roof ventilator operates without electricity, utilizing natural wind power to continuously exhaust air throughout the day. It provides an energy-saving solution with no risk of electrical failure, offering silent and maintenance-free operation. The ventilator features a tube diameter of approximately 4.33 inches (11 cm) and a turbine diameter of approximately 7.48 inches (19 cm). Its optimized design allows for rapid and effective air exchange, helping to prevent moisture buildup and stale air in enclosed spaces. Ideal for residential and light commercial use, this ventilator is suitable for installation on factories, farms, workshops, kitchens, roofs, and homes. It supports consistent airflow and is especially useful in chimneys or vents that are not frequently used, contributing to a more comfortable indoor environment. Despite requiring no electricity, the ventilator delivers reliable and efficient air exhaust within minutes. It helps protect the surrounding area from rain and excess moisture while maintaining quiet operation. Enjoy silent ventilation performance with this non-power roof ventilator. Its seamless design promotes rapid air circulation without generating noise. Made from durable stainless steel, it offers rust-resistant and heat-resistant properties for long-lasting service. Size: Tube diameter: approximately 4.33 inches (11 cm) Turbine diameter: approximately 7.48 inches (19 cm)