Ubaidullah bin Muhammad al-'Aishi عبيد الله بن محمد بن حفص العيشي · The Book on Clothing

"The Messenger of Allah (ﷺ) had a ring made from silver, so he had 'Muhammad, the Messenger of Allah' engraved on it. Then he said: 'Do not engrave with it.' This Hadith is Sahih Hasan. As for the meaning of his saying: "Do not engrave with it" - he was prohibiting that anyone have "Muhammad, Messenger of Allah" engraved on his ring.