Specifications: Product: Chimney Cowl Cap. 1x Roof Fan Chimney Cowl Cap. ★Change Indoor Air, Purify Indoor Air, Very Suitable for Wind Conditions, and Can Be Used for All Types of Ventilation Slots. ★Using the Air and Thermal Convection Caused by Natural Wind and the Difference Between the Internal and External Temperature to Drive the Turbine to Rotate.
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