To use like this or with Model 2 Part 1 or Part 2. You just have to glue the part you choose to get a more personal touch on your ring.
Part 1: https://www.shapeways.com/product/XTN4845AG/ring-model-2-part-1
Part 2: https://www.shapeways.com/product/ZU6RRVAAG/ring-model-2-part-2