Watch List notes:

PHRYGIA. Docimeium. Diadumenian, as Caesar, 217-218. Tetrassarion (Bronze, 29 mm, 10.03 g, 7 h). M•OΠEΛ•MAKPI•ANTΩN•ΔIAΔOYMENIANOC•K Bare-headed, draped and cuirassed bust of Diadumenian to right. Rev. ΔOKIMEΩN MAKEΔO-NΩN Diadumenian (?), radiate, on horseback to left, raising his right hand in salute and holding whip in his left. BMC -. Megaw -. Naumann E-Auction 90 (2020), 341 (same dies, but whip on reverse overlooked). SNG Copenhagen -. SNG Leypold -. SNG Righetti -. SNG Tübingen -. SNG von Aulock -. Extremely rare, apparently the second known example. Good fine.