Q. One who does not wear Rabbenu Tam’s Tefilin by mistake dropped his friend’s Rabbenu Tam’s Tefilin. Does he have to fast?
A. Horav Shlomo Miller’s Shlit’a opinion is that he does, since those Tefilin carry the same name’s of Hashem and Parshios, just in a different order.
Rabbi A. Bartfeld as revised by Horav Dovid Pam, Horav Aharon Miller and Horav Chanoch Ehrentreu Shlit’a.