The very first prototype GI Joe toy is the star lot of Heritage Auctions' August 10 Entertainment & Music Memorabilia Signature Auction in Dallas.
The 12 inch tall 1964 handcrafted mock-up of the Real American Hero is described by the auction house as "simply the most prized collectible there could be for generations of men".
Its first appearance at auction was through Heritage Auctions in 2003, when it was sold for $200,000, securing a place in the top 10 most expensive toys list.
Heritage states that it expects the prototype to exceed this sum again, but has placed a modest estimate of $125,000+.
"There are few more hallowed pop culture artefacts that could come up for auction than this," commented Heritage Auctions' executive vice president, Ed Jaster.
The prototype was crafted using a plastic body with wire-spring joints, a hand-painted plastic head that was created by pulling a mould from a carved wooden original, and a hand-sewn uniform, complete with a set of hand-stitched chevrons.
It was the brainchild of Don Levine, as creative director at Hasbro in the mid-1960s, who developed the idea first offered by licensing guru Stan Weston. Weston was convinced that boys would play with dolls just as much girls; it just had to be the right doll and called an "action figure".
A further two early GI Joe action figures join the sale. The first is a prototype of the first GI Joe to be dressed in an Air Force uniform (1964), and the second an early production model of the GI Joe Navy Talking Action Figurine (1967). Both are valued at $12,500+.
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