4inch Pipe Exhaust Fan Adjustable Speed Duct Fan Kitchen Window Airflow Blower Booster Air Ventilator Pipe Ventilation Extractor ,Energy-Efficient

Adopting cutting-edge DC DC variable frequency motor technology. variable frequency brushless high efficiency motor and double bal bearing, the power consumption is only half of that of ordinary AC motor Blade desion originates from the aircraft engine with supercharging structure. according to the aerodynamic force Theory, output wind pressure and larger air volume Intelligent enhanced steady current technology, supports ovnizeble DC 12V/24V and other power supply voltage Pass IPX 4 waterproof test to ensure the normal operation of the fan in harsh and humid environment There is no noisy sound, only soft wind sound, the noise is no morethan 56.8 decibels, further enioy the comfortable environment offresh air