Ah, okay. That makes significantly more sense. :]
But then I come to the question as to how the Tunnel Snakes in Vault 101 obtained those special jackets, does the vault have the material to create clothing like that? Is it something simply not fitting into Fallout's cannon? Or is it just clothing the first vault dwellers might have brought with them, only messed with a bit?
That's a question I don't know the answer to, though I suppose it's possible that the people who originally went into Vault 101 brought some leather jackets with them, why? I don't know. But considering the presence of BB guns, switchblades, comic books and such in the vault, it seems that vault dwellers were able to bring some personal possessions that weren't vital to the normal operation of the vault, and the Tunnel Snakes just decided to use them and modified them somewhat to suit their needs. Either that, or it's just one of those things that really doesn't have much of a logical explanation for it, and when you find yourself wondering about it, the only thing you can really do is repeat to yourself "It's just a game, I should really just relax." Either one works for me.
I certainly doubt they were custom made in the vault, since they look like leather jackets to me and I don't see any cows in the vault, unless it's some form of synthetic material that has the texture and look of leather but can created using the facilities in the vault, I suppose. Which maybe could be true.