Samsung NX to M39 lense mount adapter. About M39: http://en.wikipedia.org/wiki/M39_lens_mount I built it for a Jupiter8 from an old Soviet Mir camera. Flange focal distance is 25.50mm (NX) vs 28.80mm (M39), so the fit is very tight and unfortunately the lense needs to be stopped down to get infinite focus. I printed it with layer height of 0.1mm and a 0.4mm nozzle on a Delta printer. Use it as you like.