There's No Way to Kosher Avodah Zarah
Unfortunately, wigs have become a very popular trend in modern day orthodoxy. Most B’not Yisrael (Jewish women) that use sheitels have no idea where these beautiful “hair coverings” really come from.
The truth is that over 98% of all wigs in the market today come from places of Avodah Zarah (i.e. the idol worshipping temples of India). Yes, this is the case despite having a Kosher certification saying that they were “Made in Europe/Brazil or other countries”.
This is the only part of the Jewish industry that has a single entity certifying Kashrut, as everyone knows there is no way to kosher Avodah Zarah without lying. Over 25 million men and women in India sacrifice their hair (tonsure) to their deities in idolatrous temples each year, creating an unlimited market supply of top quality hair.
The temples then take this hair they received for free and sell it to European, Brazilian, American, etc. companies, which thereby use it to make the very same sheitels carried by your local sheitel machers.
Even a Single Strand is Forbidden
Remember that the Torah strictly forbids ever benefitting from Avodah Zarah, and that there is no way to make is Kosher. A hair that was tonsured and sacrificed is then absolutely forbidden by the Torah, since it’s considered as a benefit of an act of Avodah Zarah. This literally means that even if a wig has only a single strand of hair from these idol worshipping temples in India, the wig is now considered a benefit of Avodah Zarah.
As a secondary note, we all know that even in the absence of idolatry, the wigs being marketed today are completely immodest and forbidden even by the Poskim that permitted wigs (before the discovery of their Avodah Zarah roots).
Please watch all of the videos on our playlist and see the many educational shiurim made by our own Rabbis about this topic, as well as short clips by the G’doley HaDor that discussed it, such as Rav Ovadia Yosef zt’l, Rav Shalom Elyashiv zt’l, Rav Shalom Shwadron zt’l, Rav Shmuel Wosner zt’l, Rav Chaim Kanievsky shlita, and more.