p. 31 Chapter Ten Al HaShulchan
2. Unwoven garments such as those made of leather, plastic or similar materials are not obliged to have zizit. However, if one wove a garment with plastic thread then it is obliged and its zizit should be made of sheeps' wool (Ben Ish Chai Noach 3 and later authorities).
Note from us: Please consult your own rabbi to find out what to do - these are for learning purposes only.
As quoted from:
Shulchan HaMelech, a Kitzur Shulchan Aruch in 3 volumes as compiled by Maharan HaRav Shmuel Laniado z'al, 1923 with the supplement "Al HaShulchan" containing various opinions compiled by Ezra Basri, Chief Justice of the District Court, Jerusalem in 1992.
We would like to dedicate this learning for the speedy and complete recovery of two people: our friends' 5-year-old son, Joseph Benjamin, son of Ireneusz Khrystof, diagnosed in April with ALL leukemia, and a longtime friend of the family, Frank, son of Joseph, having thyroid surgery soon. Please have them in mind when studying. If you would like updates on their progress, please let me know so I can tell you when I find out from either or both.