I tried several different versions of this kind of thing but none of them worked with my snippers so I decided to make something that hopefully works for anyone.
Very quick and simple print, no supports needed.
The pictures are of the version I printed, I reworked the model slightly to make it parametric. The stl I have uploaded is the reworked version and the F3d file is attached.
There's only one value to adjust as you might need to make it longer overall.
The author marked this model as their own original creation.