Sufyan mentions a similar hadith, and in it there are some additional words: He said: O Abu Ishaq! What you are wearing is partly silk and partly something else, that is, woollen cloth (khazz). He said: What touches my body is the woollen cloth.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب صلاة الخوف / 6071