Air Systems International Single Speed Electric Blower Kit includes 8" SVB-E8 blower and SV-CUP Saddle Vent ventilation kit. It has 8" air duct that is installed on the bottom of The Saddle Vent and run to the bottom of the manhole. Duct permits fresh air to be supplied to the workers and removes any harmful gases that may be deadly for the occupants. 90 deg elbow displaces the severe kink in the air duct and permits for rotation of the intake duct to any desired position at the street level.