THIS IS VERY EARLY WORK IN PROGRESS, IF YOU WANT A PROVEN SOLUTION GET THE SLA ENCLOSURE INSTEAD.

MDT/X-SLM-BOTTOM

This is supposed to be printed with Selective Laser Melting (SLM) Process (Aluminium)

It will fit MDT or MDTX.

Make sure to select SML as well as:

Threads and Tapped Holes: Do your parts need to tap threads? YES

If a dialog comes up to add a technical drawing, add this image:

Since this enclosure has the same outer dimensions as the SLA print, you have to be specially careful about possible short circuits (since this enclosure is made out of conductive metal).

Use a continuity tester or other electrical tool of your preference (oscilloscope, multimeter) to make sure none of the soldered pins on the bottom side of the MDT/MDTX PCB make any contact to the metal enclosure bottom. Inspect your PCB from the backside if there is any pin that can be shortened to avoid making any contact to the metallic enclosure.

Any short from any PCB pin to the enclosure will lead to a non functional device and could kill your Teensy or other electronic components on the PCB instantly. If you have any doubts that you can reliably check and resolve any possible shorts or do not want to deal with this complication at all, please do not buy this but go for the SLA enclosure (that is not conductive at all) or the Sheet Metal enclosure, which has way larger safety distances build in place. 

This is the corresponding other enclosure part:

https://www.pcbway.com/project/shareproject/MDT_X_SLM_LID_317667e9.html