This is a blank envelope model for remixing and creating your own envelope design. 

It doesn't require any glue.

The folded dimensions of the envelope are 165 x 80 mm.

It's the base envelope I made for the Eid envelope I uploaded a while back - an example of the kinds of things you could make: 

Step File

There is a step file which you can edit in CAD software of your choosing. The template is intended to be printed in two 0.16mm layers with the outer surface face down on the bed, unless you have stuff sticking out of your envelope in which case the inner surface will be on the bed. In both cases the fold lines, which are only one layer thick, should be on the bed surface.

Folding the template:

1. Peel gently off the build plate. 
2. Fold the two sides inwards along the fold lines 
3. Fold the bottom inwards along the fold line
4. Insert the two tabs on the bottom into the sides
5. Fold the top along the fold line
6. Insert the top tab to close