A number of public authorities, including the BaDaTz of the Eida Chareidis and HaRav Shlomo Machpud, have issued public warnings about talleisim and tzitzis manufactured in China. They write that talleisim and tzitzis imported from China without any reliable kashrus supervision constitute a severe stumbling block to the public.
Even though some have some kind of hechsher, it was found that most of their material is polyester designed to look like wool. In addition there is the suspicion of their containing shatnez.
The strings of tzitzis imported from China come from doubtful sources. One must be careful to purchase tzitzis only from a reliable source produced in Israel. The BaDaTz adds that this is especially true of the tzitzis strings which need a special hashgochoh since they are used to fulfill a Torah-based mitzvah.
