for several vehicle concepts:

Saturn S-II-4

Four engine version planned as the Saturn C-4 second stage (1960 study).

Saturn S-II-8

Eight engine version planned as the Saturn C-8 second stage (1960 study).

Saturn S-II-C3

The S-II-C3 stage version was studied in 1960 for the Saturn C-3, consisted of four J-2 engines and had a height of 21.30 m