The Messenger of Allah ﷺ would give the salam to his right until the whiteness of his cheek became visible, and to his left until the whiteness of his cheek became visible.
أخبرنا محمد بن آدم عن عمر بن عبيد عن أبي إسحق عن أبي الأحوص
كان رسول الله ﷺ يسلم عن يمينه حتى يبدو بياض خده وعن يساره حتى يبدو بياض خده