Technicians attach a crane to the Pump Flow Control Subsystem (PFCS) in the Space Station Processing Facility. The PFCS pumps and controls the liquid ammonia used to cool the various Orbital Replacement Units on the Integrated Equipment Assembly that make up the S6 Photo-Voltaic Power Module on the International Space Station (ISS). The fourth starboard truss segment, the S6 Truss measures 112 feet long by 39 feet wide. Its solar arrays are mounted on a “blanket” that can be folded like an accordion for delivery to the ISS. Once in orbit, astronauts will deploy the blankets to their full size. When completed, the Station's electrical power system (EPS) will use eight photovoltaic solar arrays to convert sunlight to electricity. Delivery of the S6 Truss, the last power module truss segment, is targeted for mission STS-119.