The triangle is done with stainless steel,
by W.A.Stanggaßinger, Wasserburg am Inn, Germany
Real Penrose Triangel 
Sideview 
Shadow 
Parallely to table 
View from top
Real impossible geometry: Penrose Triangel
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The triangle is done with stainless steel,
by W.A.Stanggaßinger, Wasserburg am Inn, Germany