Watch List notes:

Uncertain. 2nd-1st centuries B.C. Æ as (29.0 mm, 10.68 g, 7 h). Rome mint. Laureate head of bearded Janus; I to right / prow of galley right; overstruck with a helmet (?). Crawford ?; Sydenham ?. Fine, sandy patina. 

An interesting coin with the I to the right of Janus and a double-struck reverse. Probably over-struck on an earlier type.