A simple bottle opener that can be used immediately as a cap for classic Czech beer bottles. I don't know who would need to use a cap for an unfinished beer, but just in case… Insert 1 Kč or 10 € cent coin into the prepared hole (pause printing or paste at the end). I haven't printed it yet (my Prusa MINI is sick), but I believe that PETG is a good choice. A small size fitting may be required.

Update (2022-03-02): Slightly improved after test print. Added version with a hole for a magnet (diameter up to 22 mm, height up to 3 mm) to hold on the refrigerator.