NEX-6 + Meyer Trioplan 1:3.5 F = 2,5cm (1933; Minifex)
The Trioplan 25/3.5 was used on the subminiature Minifex, a camera made in the 1930s by Fotofex Kameras in Berlin. The camera took 36 13x18mm photos on special 16mm film. Surprisingly, the lens has no problem with the APS-C sensor.
For more information see here: