When I got my first 3D printer last year I wanted to learn to model in Fusion 360 and print useful stuff while also learning the capabilities and limits of FFF printing. So, in this design I was intentionally playing with overhangs and bridging, while still trying to keep the model easily printable.
A few key highlights of the design:
Use 3 or 4 perimeters for full strength on the grippers. Any infill 10% or better should work, since all the strength is in the perimeters.
Here's a link to the Fusion 360 model. Consider this your warning that it's the first real thing I made in Fusion (and my first attempt at parametric design), so it demonstrates some very bad technique. If I were to start the design over today I could do the same thing much more simply and cleanly, but since this one works I don't really see the point.
The author marked this model as their own original creation. Imported from Thingiverse.