This is universal milk box holder, that should fit most of milk boxes or other boxes that have paper notch on the end. It holds full 1 liter box without a problem even when printed on bad settings (as I did for this test :) ).
Tested on Czech boxed milk, but should fit on others as well.
Printed with supports, check 3mf file in files section.
The author marked this model as their own original creation.