[9/7/2016] Design update: 1. Separate it into two parts: one black body, and one color ring. Print the ring in T* orange! [8/18/2016] Design update: 1. Better light seal 2. Now you can print with only base support. And it is super easy to remove. [Initial release] The Rolleiflex SL26 came with three excellent Carl Zeiss lenses: 40mm f/2.8, 28mm f/3.2 and 80mm f/4. However the rear elements of the lens is attached to the body, only the front elements are interchangeable. You can disassemble the rear element from the body. It is very easy. With this adapter, you can marry the rear element to a readily-available L39-NEX adapter, so you have a durable assembled lens to use. See the attached photos for the look, as well as a few shots I took on my Sony A6000.