Four Intersecting Triangles by Tung Ken Lam
Number of units: 12 (4 colors, 3 pieces per color).
Designer: Tung Ken Lam
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This model is quite easy to fold and to assemble. In fact, I recommend that WXYZ should be the first 'Modular Origami' model that a beginner should fold. Took me about half an hour to finish. The overall design is `four intersecting triangles', one triangel per color. Each triangle is in a plane.