Montana Ten
A person who looks like the majority of women from Montana. This stems from the fact that the instant you cross over the border into montana, the attractiveness of the female population instantly decreases. Therefore, someone who is a ten in Montana is a five in other states. Or a three. Probably a one.
Broseph: "Hey, dude, did you go out with that chick you met on eHarmony?"

Brohommed: "Yeah, but her profile pic was fake, she was a total Montana Ten."

Broseph: "Lol! Are you going to see her again?"

Brohommed: "F**k that, I'm not going to even talk to her"