Who is the mashgiach on the process making sure it’s lishma, etc.? Who gives the official hechsher?
R. Eliyahu Tavger is the Rav of the Amuta. The workers doing the dyeing, spinning, twining of the threads are all yirei shamayim Jews who are very careful to state explicitly before every process, “L’shem mitzvat tzitzit.” – Mois Navon.
Rav Avraham Rubin gives a Badat’z hechsher on all our strings and processes. You can read the hechsher here.