I see many Chaba"d shluchim have Jews put in tefillin. Wonderful work their doing. However, I read this in Aruch Hashulchan O.C. 27:20:
ומקום הנחת תפילין של ראש מהתחלת עיקרי השיער שעל המצח עד סוף המקום שמוחו של תינוק רופס ויש להזהיר לההמון על ככה, כאשר ראינו בעינינו שרבים נושאים השל ראש חציו על המצח. ואוי לאותו בושה, כי לא קיימו מצות תפילין מימיהם, ומברכים לבטלה, ועונשם גדול
Summarizing the above:
The proper place for the tefillin shel Rosh is from the top of the hairline until the point of where a baby's forehead is soft. One should be especially careful about placing the tefillin in the proper place, for if not, this is a terrible embarrassment to the mitzvah, they have made a blessing in vain and the punishment is great.
My question - the tefillin shel rosh strap is one size. Are the Chaba"d shlichim adjusting the strap for each person's head before they have that person say the bracha? If they aren't, how can they let that person say the bracha?
I see many Chaba"d shluchim have Jews put in tefillin.
These must be large tefillin to fit a whole person!