Fragments of A Penrose Triangle

These appear to be reasonable fragments of 3-D objects

-- -- -- --


These two appear to be pictures of impossible objects, yet we
see all the relationships between the parts that are locally
possible even though globally they are impossible.
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This is another view showing the actual structure of the object
from a different viewpoint



Here is a video showing how to make such a thing.
(Apologies for adverts)
http://www.videojug.com/film/how-to-make-an-impossible-object

Stencil for paper shape to be used.