Transparency is not only an aesthetic question for some parts, it is also a functionality. Which transparent material do you need? There are MEX (also called FDM) materials that allow for transparency, but for a good finish, it needs some postprocessing through a solvent or coating. The VPP (also called SLA) technology allows for almost glass like transparency with some materials.
If you are unsure about what to take, contact us and we will try to realize your part.