Workshop of Robert Campin, ‘Annunciation Triptych (Merode Altarpiece)’, ca. 1427–1432, The Metropolitan Museum of Art

made in Tournai, South Netherlands; overall (open): 25 3/8 x 46 3/8 in. (64.5 x 117.8 cm); central panel: 25 1/4 x 24 7/8 in. (64.1 x 63.2 cm); each wing: 25 3/8 x 10 3/4 in. (64.5 x 27.3 cm)
http://www.metmuseum.org/art/collection/search/470304

Image rights: The Metropolitan Museum of Art (The Cloisters Collection, 1956), licensed under CC0 1.0 Universal