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MTV-7 Multi-Terrain Vehicle

The MTV-7 Multi-Terrain Vehicle was a one-man ground vehicle on two large wheels and one 
blaster cannon used by the Galactic Empire.

Its wheels could stretch forwards and backwards so that the vehicle became a lot shorter. 
It was used during the Battle of Hoth.

Behind the Scenes

The MTV-7 is a vehicle designed and released by Kenner in their Mini-Rig series in 1981. 

Sources

- Star Wars: The Action Figure Archive