There is a model named the Flower of Twist. (Refer to https://www.shapeways.com/product/CHQ3EVG6F/flower-of-twist-pendant
) While this model is about arrangment of six-membered rings, the Seed of Twist is dealing with special identical four-membered rings put together in a very special manner.
Note that the edge angle is not a 90 degress. It is smaller, approximately 82 degrees. Its exact value is arccos(1/7).