The following is an exchange with a prospective customer who seems to be debating whether he wants to wear a cotton tallit katan or a wool tallit katan. Although I found some of his questions a bit surprising, I think the exchange may be instructive for some other people out there interested in buying a tallit katan.
With wool tallit katans, do I wear it against my skin? What is the general custom for wearing one? Thank you for your time.
No, you can’t wear wool against your skin (try it and you’ll see what I mean). Even our Wool Comfort undershirt style tzitzit is not meant to be worn against your skin. You need an undershirt. It is made from a very soft wool, but it’s still itchy.
(I once told a customer who asked a very similar question that there’s no such thing as wool that can be worn against the skin. I was wrong. He was from New Zealand, which is one the the world’s leading producers of wool, and he gave me a quick lesson on Merino wool.)
People who don’t like to wear three layers choose a cotton undershirt style tzitzit garment.
How would I wash the wool undershirt tzitzit?
Personally I wash mine by hand, but I think woolite and a gentle cycle, cold water should be fine. The real problem is the tzitzit. Even on a gentle cycle they can get horribly tangled. Did you even buy one of these? If not, there are ways to improvise. You can tuck the tzitzit into a sock and tie it up tight and wrap rubber bands around it.
Thank you very much for the response. I know someone who wears the wool against his skin and he is an observant Jew. So I wasn’t sure if it was against halacha or not. Are there special undershirts for wool katan use? Or can just any cotton shirt work?
What if they made wool katans with a special thin soft lining that is only on the inside. The inside that touches the skin? But without commiting shatnez? It would be interesting. It beats 3 layers.
If I may ask, what is it that you wear? Do you wear wool katans?
I have both cotton and wool.
There are some opinions that wearing the garment against your skin (cotton or wool) is inappropriate. Not against halacha, strictly speaking, but sort of showing a lack of respect for a mitzvah item. But a tallit katan is in essence a regular garment, so it does not have the kedusha of items like a mezuzah or tefillin. According to that opinion, which is a stringency that not all poskim concur with, because a tallit katan is used specifically for the mitzvah of tzitzit, it’s more than just a regular garment. These opinions state that an undershirt is meant to absorb sweat, so creating a tzitzit garment that serves that function is disrespectful.
Shatnez is not an issue here because the fabrics involved here are wool and cotton. The prohibition is against a combination of wool and linen. Cotton and linen are not the same thing. Linen is made from flax/linseed.