That's the modern sports variant. The traditional one is better suited for transporting stuff and one or even two passengers as well:
http://www.esla.fi/fin/potkukelkka.html
In good conditions this can be amazingly fast, and two people can alternate so that one pushes the sled and the other one rests on the seat.
In good conditions this can be amazingly fast, and two people can alternate so that one pushes the sled and the other one rests on the seat.