Construction workers with JP Donovan attach a heavy-lift crane to the Interim Cryogenic Propulsion Stage Umbilical (ICPSU) to prepare for lifting and installation on the mobile launcher (ML) tower at NASA's Kennedy Space Center in Florida. The last of the large umbilicals to be installed, the ICPSU will provide super-cooled hydrogen and liquid oxygen to the Space Launch System (SLS) rocket's interim cryogenic propulsion stage, or upper stage, at T-0 for Exploration Mission-1. The umbilical will be located at about the 240-foot-level of the ML and will supply fuel, oxidizer, gaseous helium, hazardous gas leak detection, electrical commodities and environment control systems to the upper stage of the SLS rocket during launch. Exploration Ground Systems is overseeing installation of the umbilicals on the ML.