"Endeavour" carried a wide variety of equipment and cargo in the payload bay, with the largest item being the "Kibō" Japanese Experiment Module Exposed Facility (JEM EF), and the "Kibō" Japanese Experiment Logistics Module – Exposed Section (ELM-ES). The exposed facility is a part of "Kibō" that will allow astronauts to perform science experiments that are exposed to the vacuum of space. The exposed section is similar to the logistics module on the "Kibō" laboratory, but is not pressurized. Once its payloads were transferred to the JEM EF, the ELM-ES was returned to the payload bay.