Summary

I modeled this with Fusion360. It has a removable handle for easier storage. You can use a string to tie the peg to the carrier. I purposely designed the handle to fit loosely in the carrier, so if I lifted it without the peg in place, I would just have a handle in my hand and not coffee all over me. I printed it with PLA and tested it for 20 minutes with hot water in the McDonald’s cups and it only sagged about .5mm. I know it also works with cups from Dunkin and 7-11, but I did not test those cups for the extended 20 minutes. The carrier fits over the cup carriers in my car (2017 VW Golf Alltrack).

Printer:
Ender3

Walls/Top/Bottom:
5 layers each

Infill:
Carrier 30%

Handle and Peg 100% infill