... FOAM BOXDelivery Detail:30DAYSSpecificationsTight structure and small volume,Wide range of speed adijustment,smooth starting&low current starting,Low ... more tight,especially axial dimension minish.2,Wide range of speed adijustment,smooth starting&low current startingSpecial squirrel ... smooth starting and low current starting and smooth speed adjustment.3,Low noise&small vibration4,High running ...