This is a hub trial, in copper, for the 1876 Paquet reverse used on J1475A-J1475B/P1627-P1628. This used to be J1320-J1321 in earlier editions of Judd.
Only 2 are known, both ex Brand, Bowers and Merena 3/90. The illlustrated piece was last offered in the Stacks-Bowers 8/11 and 8/13 ANA sales.
Photo courtesy of Stacks-Bowers.