This is a rugged and discrete AirTag case. Great for putting into your luggage, in a backpack, under a car seat, etc.

I used a cable style keyring such as these https://a.co/d/afOPQ5t.

I found that the 6.5" (165mm) cables work the best.

If the case is printed using a high infill (in my case I used 40%) it will be very strong, even using PLA.

The screws I used were 3mm x 10mm.

Hopefully something like this, especially if attached to something difficult to cut, will deter a would-be thief. It will be difficult to just pull off. And I don't know of many thieves that go around with a 2.5mm Allen wrench in their pocket.