Yevamot 103A

בין עומד, בין יושב, בין מוטה, והחולצת מן הסומא ⁠— חליצתה כשרה. אבל במנעל הנפרם שאין חופה את רוב הרגל, בסנדל הנפחת שאינו מקבל את רוב הרגל, ובסמיכת הידים, ובאנפיליא של בגד, וחולצת מן הקטן ⁠— חליצתה פסולה.

whether the yavam is standing or sitting or leaning; and a woman who performs ḥalitza on a blind yavam; in all of these cases her ḥalitza is valid. But if she performs ḥalitza when he is wearing a shoe that is so torn that it does not cover most of the foot; or using a broken sandal that does not hold most of the foot; or using a hand blanket that the amputee wears on his hands, similar to a leather shoe, in order to drag himself using them; or using a soft shoe [anpileya] made of cloth; or a woman who performs halitza with a yavam who is a minor; in all these cases her ḥalitza is disqualified.

קב הקיטע, מני ⁠— רבי מאיר היא, דתנן: הקיטע יוצא בקב שלו, דברי רבי מאיר. רבי יוסי אוסר.

The Talmud comments: Who is the tanna who holds that an amputee’s prosthetic is considered a shoe? It is R' Meir, as we learned in a Mishnah (Shabbat 65b): One with an amputated leg may go out on Shabbat with his wooden leg, as it has the legal status of a shoe; this is the statement of R' Meir. He reasons that the prosthesis functions like the shoe of any other person, indicating that R' Meir is not especially concerned about the material from which the shoe is made. And R' Yosei, on the other hand, prohibits the amputee from going out on Shabbat with his wooden leg, as he does not consider it a shoe that is being worn, but rather a wooden object that is being carried.

באנפיליא של בגד, אתאן לרבנן!

The Talmud asks how R' Meir can be the tanna of the baraita, as the continuation of the baraita states ḥalitza is disqualified if performed with an anpileya made of cloth, as this cloth shoe is not to be considered a shoe. If so, have we come to the opinion of the Rabbis, who rule in accordance with R' Yosei, and render it prohibited to use any shoes for ḥalitza that are not made of leather?