It would help if you told us where you received the strings from maybe. It looks like to me just some synthetic gut. Have you played with it yet? Try stringing up a racquet with the strings and give some feedback on that if your able too.
Racquet : TGK238.1 2X / Head YTPP 1X
Strings : BHB7 17G 49lb / LUX 4g Rough 17G