Split up specific stls for printing with different colors in case you have an MMU or equivalent.
In my case, I only had white filament in PETG while my black/grey/blue is PLA and they don't play well together; I don't recommend it, but it can be done. So the stls are split up with a more mechanical fitment in mind; just an fyi in case you're wondering why they're split strangely.
Original model by Martin Taichl.
The author remixed this model.