This is a 1973 XS size deadstock liner for the M-65. It's for the M-65 fishtail parka. The buttons have been custom-added at a vintage shop so that the liner can be worn on its own. You can fasten it in the front, and it can also be attached to the shell without any issues. The buttons are not the flat buttons like those used on the 1968 shell, but they are the type of buttons used on shells from 1970 onwards, showing a real attention to detail. While XS shells are available, it's difficult to find an XS liner. I get the impression that many people are struggling to get liners even on Mercari. I often see comments on XS full set listings asking, "Can I buy the liner only?" Of course, they are usually turned down. A deadstock liner is even harder to find. And one with custom-added buttons is even rarer and impossible to get. Please purchase only if you understand vintage items and genuine US military items. Please resolve any questions before purchasing.