The Cadillac Series 36-60 was Cadillac's entry-level product in the luxury vehicle market when it appeared in 1936, competing with the entry-level Packard Six. Each model year added the year prefix to the series (37-60 and 38-60) in the number hierarchy used at the time. It was replaced by the Series 39-61 in 1939, but a model that was derived from it, the Sixty Special or 60S, continued off and on through 1993.