AC external rotor motor powered backward-curved centrifugal fan series covers a diameter range from φ133 to φ560 mm, with maximum air volume up to 8,500 m³/h and maximum static pressure up to 650 Pa. This external rotor fan series has a compact structure, operates reliably and is both energy saving and efficient. It is designed with low noise, a long service life, and is easy to install.After years of independent research and development, we now have available high performance, and low noise level, one-piece injected plastic impellers, with a diameter range from φ133 to φ250 mm.