In this answer, it says there is a reference to Spider-Man undergarments in Captain America: Civil War trailer.
Are these undergarments (the Spider-Man ones in the answer I shared above) specific to Marvel Universe (known in Marvel comics or movies) or Robert Downey Jr. made a reference to the real world product by calling it in the trailer? Is this a 4th wall thing?
I know that these undergarments can exist in any universe. These are undergarments for pity's sake... Please be productive with your comments and answers and avoid commenting on obvious things.