Weiworld Passive Air Vent 4 inch for Fresh Air Environment Energy Efficient Fresh Air Intake Vent with Aluminium Telescopic Duct & Exterior Stainless Steel 304 Grille (No Motor)

Passive Air Vent is a natural ventilation method that does not use mechanical systems. It uses the pressure difference generated by natural forces to introduce fresh outdoor air into the room and exhaust the indoor polluted air. Passive Air Vent helps to improve indoor air quality, reduce humidity and pollutants, and protect you and your family's health Passive Air Vent can save energy and cost, because it does not need electricity and has no operating cost. It can reduce the dependence on air conditioning and heating, lower carbon emissions, and protect the environment. Passive Air Vent can automatically adjust the air flow rate and direction according to the indoor and outdoor temperature changes, achieving the best ventilation effect. It can also reduce noise and dust, allowing you to enjoy a quiet and comfortable living environment Easy to Install, just need to open a small hole in the wall or window, and then insert the vent. Please wear protective gloves before installation to prevent being scratched by sharp edges Easy to Clean and Rreplace the Mesh Filter: Rotate the round panel to the left until the panel are completely separated from the vent cover ,and then pull out the retainer upwards to clean or replace the mesh filter inside.