Сатурн-1Б
By sharing the S-IVB upper stage, the Saturn IB and Saturn V provided a common interface to the Apollo spacecraft. The only major difference was that the S-IVB on the Saturn V burned only part of its propellant to achieve Earth orbit, so it could be restarted for trans-lunar injection. The S-IVB on the Saturn IB needed all of its propellant to achieve Earth orbit.