Battery adaptor 18650 to D cell

I have made these two parts to convert my 5D Maglite into a 3x 18650 LED Maglite.

Adapter slides nicely over the 18650 batteries.
For 5D→3x18650 conversion you will also need to print the included 100 mm spacer.
There is a bit of additional assembly needed for the spacer to create the electrical connection and this design is made to accept two M4 thread inserts so that two sides could be easily connected with electrical wire.

If you're doing a different conversion you will likely need to change the spacer length to fit your needs:
e.g. 3D → 2x18650 needs ~55mm spacer.
4D → 3x18650 needs ~35mm spacer.
6D→ 3x18650 needs ~165mm spacer.