The Formula One F duct is a rear wing stalling device that operates by directing air flowing onto the car's nose cone through a tube around the cockpit and to the centre of the rear wing.
The driver can elect to block the air using his left leg, allowing him to stall his rear wing and thus increase the car's overall straight line speed.
For more information on F ducts, visit: http://www.formula1.com/news/technical/2011/0/823.html
USE IN FORMULA ONE
Formula One first saw F ducts used by the McLaren racing team in the 2010 racing season.
The device was instantly the envy of rival Formula One teams as it offered McLaren a serious advantage over other cars.
McLaren demonstrated the advantage of their controversial F duct system by taking podium places at the first two races of the season before sealing a one-two at the Chinese grand prix.
Formula One's leading teams worked hard to develop their own F duct systems in order to compete with McLaren, and achieved this later on in the season despite knowing that the aerodynamic system would be banned during the 2011 Formula One season.
Formula One banned F ducts just five races into the 2010 season once their performance level was demonstrated by McLaren.
The ban was agreed by the Formula One Teams Association (FOTA) due to the high costs associated with developing and refining F duct systems.
Although F ducts remain a technically legal piece of equipment, the ban imposed by FOTA means that it is extremely unlikely that they will return to the sport for the foreseeable future.