I was trying to find an image reference for what different clipper guard lengths look like. Every single reference I found had different models with different hairstyles, or used illustrations instead of photographs.

After searching a bit, I found this video, which shows the same person with different hair lengths, with the hair uniformly short over the whole head.

I think it's quite interesting that a random YouTuber may have created a best-in-the-world reference, even if it's for something as mundane as haircut lengths.