Original 1st printing 12&1/4 x 19&7/8" (thin margin version) concert poster for rock n' roll pioneer Bo Diddley appearing with the Sons of Adam on 8/5/1966 and again with the Sons of Adam and Chicago blues legend Little Walter on 8/7/1966, both at Longshoreman's Hall in San Francisco, CA (*according to what I've found, these shows were most likely canceled/rescheduled).
Art by (and SIGNED in pencil by) Stanley Mouse, image ("Three Men in a Boat") is # 20 in the Family Dog/Avalon series. (*Unlike most of the early numbered FD posters, this poster was never reprinted)