RL10B-2 is a restartable liquid-hydrogen/liquid-oxygen upper-stage engine with an extendible nozzle, used on Delta IV and the SLS interim cryogenic propulsion stage. On Artemis I, a single RL10B-2 powered ICPS through perigee-raise and translunar-injection burns. NASA identifies its Artemis I thrust as 24,750 lbf, approximately 110 kN.