Side wall of UF5X0 quadcopter airframe's dirty part. It is used to protect the internal equipment in dirty part, e.g. ESCs. Its height is 15mm to accomodate 40A ESCs I use.
Because I plan to make this thing via 3D printing and the strength of 3D printed part is not strong enough, I made 4 holes to insert the heavy-lifting aluminium alloy cylinders.
This model is made by LibreCAD and FreeCAD.