'Umar wrote to 'Utbah b. Farqad that the Prophet ﷺ forbade (wearing) silk except so-and-so, and so-and-so, to the extent of two, three, or four fingers.
أَنَّ النَّبِيَّ ﷺ نَهَى عَنِ الْحَرِيرِ إِلاَّ مَا كَانَ هَكَذَا وَهَكَذَا أُصْبُعَيْنِ وَثَلاَثَةً وَأَرْبَعَةً