Yevamot 104A

ושל עיר הנדחת, ושל זקן העשוי לכבודו ⁠— לא תחלוץ, ואם חלצה ⁠— חליצתה פסולה.

or a sandal belonging to an inhabitant of an idolatrous city, a city the majority of whose inhabitants committed idolatry, which stands to be destroyed with all of the city’s property; and likewise, the sandal of an Elder made in accordance with his dignity to be worn upon his death as part of his shroud, i.e., it is not meant for walking as a normal shoe, the yevama may not perform ḥalitza using any of these shoes. And if she did perform ḥalitza, her ḥalitza is invalid even after the fact, as these are not halakhically considered shoes.

אמר ליה רבינא לרב אשי: מאי שנא זקן העשוי לכבודו ⁠— דלאו להילוכא עביד, דבי דינא נמי ⁠— לאו להילוכא עביד!

Ravina said to Rav Ashi: What is different about the sandal of an Elder that is made in accordance with his dignity that one should say that even though it is the proper size for his foot, it is not valid because it was not made for walking, but merely for him to wear after his death. But the court’s sandal also was not made for walking, as the court kept a sandal that met all the other necessary qualifications for a sandal for ḥalitza and gave it to the yavam to be worn during the ḥalitza procedure. Since the yavam would return the ḥalitza sandal after the conclusion of the ḥalitza, therefore, the sandal was never used for walking and should be invalidated for ḥalitza just as the sandal made for the dignity of an Elder?

אמר ליה: אילו מסגי ביה שלוחא דבי דינא, מי קפיד עליה דיינא?

He said to him: If a messenger of the court had walked in the ḥalitza shoe used by the court, would the judge reprimand him? Although the court’s sandal was designed for the express purpose of ḥalitza, it may also be used for walking. A shoe designed for a dead person, on the other hand, is forbidden for any other use and is not made for walking at all, and it is consequently disqualified.