An Ariane 5G storable propellant upper stage (EPS) , minus its Aestus engine, undergoing integration at Astrium GmbH's manufacturing plant in Bremen, Germany. This view from below shows the four propellant tanks (MMH and nitrogen tetroxide) with their thermal insulation and the two helium spheres for pressurisation. The EPS carries 9.7 tonnes of propellant and provides final orbital injection for Ariane 5G payloads.