 S0 is used to route power to the pressurized station modules and conduct heat away from the modules to the S1 and P1 Trusses.The S0 truss is not docked to the ISS, but is connected with four Module to Truss Structure (MTS) stainless steel struts.The P1 and S1 trusses (also called the "Port and Starboard Side Thermal Radiator Trusses") are attached to the S0 truss, and contain carts to transport the Canadarm2 and astronauts to worksites along the space station.