Sunan Abi Dawud 2590
سنن أبي داود#2590SahihNarrated As-Sa'ib ibn Yazid: As-Sa'ib reported on the authority of a man whom he named: The Messenger of Allah (ﷺ) put on two coats of mail during the battle of Uhud as a double protection. (The narrator is doubtful about the word zahara or labisa)
Scholarly Authentication
We show the most cautious grade (weakest-wins) as the overall label. Individual scholars graded it as follows:
Al-AlbaniSahih
Muhammad Muhyi Al-Din Abdul HamidSahih
Zubair Ali ZaiSahih
In-book reference: 15:114