Decor Craft Inc / DCI launched the QuaDror geometry as toy building blocks, in two sizes (3" and 1.5") and four colors.
"The QuaDror system of blocks is devilishly difficult to explain but easy to use; so easy, that prototypes disappeared. Thus was born a toy. Donald Rattner, the owner of the Module R art and design shop in Brooklyn, was strolling the International Gift Fair in New York in January and found the QuaDror blocks." -NYTimes
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