This is a trampaboards eATB motor cover. It's constructed in two pieces so you can slide it in without disassembling the whole electric motor mount. What is nice about this modularity is that it can be easily removed, replaced or cleaned.
The design also include a thicker 3D printed block in some areas. This enable to your eATB to be parked upright on the wall without damaging the rest of the board. Making it easy to store or to carry on public transport.
PS: I've noticed that some people might experienced that printing 100% solid made it impossible to slide fitted. There will be new design to fix it.