This is a full set of wermy's 3D-Printed GBZ parts, so you can purchase them all in one go and combine shipping costs!
This 3D-Printed part makes it much easier to mount your power switch (as shown in part 2 of wermy's all-custom-and-aftermarket-part build guide: http://sudomod.com/game-boy-zero-custom-parts-guide-part-2 )
It can be used
With a 3D-printed screw bracket you can avoid the whole process of fiddling with the original screw posts and epoxy and all that measuring to get it just right:
These help hold your buttons in place, prevent them from rotating, and limit how far they can protrude (so they match how far the A/B buttons can stick out)