The second picture shows what is to be in the package of each individual one. They have not been used but I'm not sure about true to size. I got these in a box at an estate sale.
I take it that someone bought these years ago and only used one string. I do not play so I do not know. I got these off of an estate sale and none of them look used.
It's very possible they did only use one string. Some people but true guitar would replace the whole guitar. Being said that, it's probably the high e string. It usually breaks first