This is a bike license plate with a metal piece to attach it to a bike. The number on the plate is 5095. The license plate measures 2" (h) x 3" (w) x 3" (d).
Lexicon
Nomenclature 4.0
Nomenclature Primary Object Term
Plate, License
Nomenclature Sub-Class
Land Transportation Accessories
Nomenclature Class
Land Transportation T&E
Nomenclature Category
Category 07: Distribution & Transportation Objects