Apple Airtag bike case

A pretty hard to open and remove case, unless you have the right tools.

it's designed for under a bike saddle but it can go wherever there is a ~7mm diameter shaft

Uses m4 screwholes, 8mm long would be best.

Printing it in black will hide it better.

Print with PETG

No supports needed

Would recommend slicing it yourself (gcode is mostly there to give a rough estimate of time and settings)