The existing AMS dryer pods by STprinting are great for the outsides. For the middle slot, I needed something to fit my Xiaomi Mija Hygrometer, of which I had a couple lying around.
Based on feedback, I strengthened the grid underneath the hygrometer.
I remixed STprinting's design, but kept the overall dimensions. To make the hygrometer stick, I closed a couple of gaps to attach double sided tape. The whole pod still prints without supports.
I used PLA with 0.16mm layer height. Make sure to Z-hop properly to avoid the fragile columns to break off. Here are my detailed settings:
A Xiaomi Mija Hygrometer and some double sided tape like this M3 tape (affiliate links).