The Messenger of Allah ﷺ intended to write letters to the non-Arab rulers, but he was told that they would not accept any letter unless it bore a seal. So the Messenger of Allah ﷺ had a silver ring made, and engraved upon it the words "Muhammad, Messenger of Allah."
حدثنا محمد بن بشر حدثنا سعيد بن أبي عروبة عن قتادة
أن رسول الله ﷺ أراد أن يكتب إلى الأعاجم فقيل إنهم لا يقبلون كتابا إلا بنقش فاتخذ رسول الله ﷺ خاتما من فضة ونقش فيه محمد رسول الله
Its chain of transmission is sahih. Muhammad bin Bakr is al-Bursani, and in the printed edition it appears as Muhammad bin Bishr, which is an error. The hadith has already appeared at 12800 and 12876.