Biconcave eyepiece lens mounted in a cardboard ring covered with red marbled paper. The diameter of the lens is c. 35 mm, the focal length ‑94 mm (the negative focal length means that the lens is diverging). On the ring is the inscription "Eustachio Divini in Roma 1666 Acuto per Palmi 26," i.e., diverging eyepiece for a telescope of 26 palms (5,780 mm). The glass has a slight yellow tint and contains some bubbles and inclusions. The lens is mounted in a cardboard housing covered with red marbled paper. The tube, 107 mm long and 57 mm in diameter, has a nineteenth-century label with the same inscription as on the ring.