Optical illusion: penrose triangle key ring

Another keychain colour? Click on "customise it", then on "edit", next select another background colour. This penrose triangle on another Zazzle object? Contact us. The Penrose triangle, also known as the Penrose tribar, is an impossible object. The tribar appears to be a solid object, made of three straight beams of square cross-section which meet pairwise at right angles at the vertices of the triangle they form. source: wikipedia