Vortex 711 CFM S-Line S-800 Fan, 8" Nullify Made in USA or Imported The s-line is a revolutionary series of fans that combine energy efficiency, ultra-quiet operations and a collection of advanced technologies that deliver unparalleled performances An extremely energy efficient ac brushless motor powers the patented mixed-flow dual impellers Built with double insulated walls, noise is reduced to levels that were previously thought to be unattainable