the lid has a perfect fit for all the Elektron boxes. Even the huuge lid for Keys fits like a glove.
However, what I would suggest for backpackers: buy additionally a shell type drone bag from Amazon for 7 pounds and it protects also the sides and carries the PSU+some cables. With this combo you can commute and travel and it would take a lot of effort to break something. Some other suggestions for that: Digitakt carry bag or case