Wall-E (Waste Allocation Load Lifter: Earth-Class) is a trash compactor robot left on Earth to clean it up after the fictional company Buy-N-Large pretty much leaves the planet uninhabitable.
This figure was part of a 6 static figurine set produced for the Disney Store when the movie was released in 2008. The other robots in the set are E.V.E., M.O., Light Bot, Vacuum Bot, and Steward Bot
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This one was a tough one to find out in the internet. There is an occasional listing on Ebay for the set.