The Koenigsegg One:1 (Swedish: Koenigsegg One:1) is a mid-engine supercar designed and produced by the Swedish company Koenigsegg. The car was rebuilt based on the Koenigsegg Agera R platform and was first displayed at the Geneva Motor Show in March 2014. [2] The Koenigsegg One:1 was produced in a limited edition of 6 units and was sold out shortly after the auto show.