C.375-450 AD, the period of the fall of the Empire under invasion by the Barbarians. See https://www.forumancientcoins.com/numiswiki/view.asp?key=Military%20Belts image 7 top left for an identical example identified as Sommer type 1.A.B. Just over 1 1/4” length with sheet plate and D shaped buckle. Both securing rivets intact. Roman legionaries wore two belts, crossed, suspending, respectively, the sword and dagger.