Sforno on Leviticus 16:4/ספורנו על ויקרא ט״ז:ד׳

1בגדי קדש הם, when angels appeared in human guise to the prophets they wore these kinds of garments. This is the meaning of the expression לבושי הבדים. (Ezekiel 9,3 and Daniel 12,6-7)