פירוש על כלים 24:16

סבכות (head-nets) – a cap that women carry on their heads, made similar to a netting that has in it thin incisions.

There are three different types of hair nets:
A girl's is susceptible to midras uncleanness; A girl's hair net is made so that it can also be sat upon. Therefore, it is susceptible to midras.

של ילדה – that is appropriate for sitting, and therefore is ritually impure through treading.

An old woman's is susceptible to corpse uncleanness; According to our mishnah, an old woman's hair net is not made to be sat upon, therefore it is not susceptible to midras. Note that in 28:9 the Mishnah will teach the opposite: a girl's is susceptible only to corpse uncleanness but an old woman's is susceptible to midras. Albeck seems to think that the version preserved in 28:9 is more accurate.

ושל זקנה – her actions prove upon her that it is not fit for sitting. But in the Tosefta (Tractate Kelim Bava Batra, Chapaer 2, Halakha 10 – which teaches the reverse) it is taught that of an old woman it is susceptible for uncleanness from treading (as opposed to uncleanness from contact with a corpse), that she does not strict/particular about it and sometimes she sits upon it. But that of a young girl who is strict/particular about her vessels, does not sit upon it, and therefore it is susceptible to the impurity of contact with corpse uncleanness.

And [the hair net] of a woman who "goes out" is free from all uncleanness. There are two explanations for a woman who "goes out." Some explain this to be a temporary hair net used by a woman who merely goes out to the courtyard. Others explain that a woman who "goes out" refers to a prostitute. Her hair net does not cover much hair so it is not considered a vessel.

ושל יוצאות החוץ (that of a whore) – a kerchief that women put on their heads when they go outside. But thee are those who explain/interpret "יוצאות חוץ"/as a whole. It is the Aramaic translation of a whore, a female prostitute, meaning to say, the head-dress of whores.

טהורות – because they are not considered a vessel. Another explanation. Head-dresses that were torn and most of the hair of woman extends outward, for they do not hold the majority of the hair of woman’s head.