Niputz Lishma strings adhere to an added stringency, where the carding of the wool is done by hand and with the express purpose of the mitzvah of Tzitzit. (Most opinions hold thatֲ this is required only from the stage of spinning and on.)
We use wool from the respected Tzitzit manufacturer, Herscovitz, in Yerushalyim for our Niputz strings.
Niputz strings are available only in Thick.
Please include in the notes on the cart page what tying method you will use. That will help us make sure we are supplying the correct length for your needs,