There was a time when I did not know what a derailleur is. And while I can probably still not spell it (or pronounce it with an honest-to-God French accent), I can now tell you that it is a part of a bicycle. Eventually, I did have to learn the word and that is how I got the idea: if I ever open a bike shop (i.e. probably never), I would like it to be as handholding as it gets for amateurs like me.

The 3D model was designed by Semyon Filippov and is available for free on CGTrader. It took a little bit of tweaking (with Blender) to group the parts and give them identifiers, so that they would be accessible through Javascript. For the final embedding I ended up using Babylon JS, which was shockingly easy to use (so kudos to the developers).