DevTerm needs a shoulder strap. I thought about modeling some strap adapters for the side knobs sealing front and back together, but then I remembered my lapsed hobby, photography, where I had backed a quick remove strap years and years ago.
Lo and behold: No 3d printing needed. Re-use what you have (-:
It’s not super ideal because the short loop of string is a bit twiddly to attach so it does not come loose, but it’s a start. Unfortunately gravity dictates that you need to unsling the strap to use the DevTerm, but maybe that’s something worth looking into …