The satellite platform is identical to that used for XMM. It provides the housekeeping equipment (power, stabilization, ground-satellite link) and hosts four payloads which simultaneously observe the same part of the sky. The four instruments in question are complementary. There are two main instruments - an imager (IBIS) and a spectrometer (SPI) - but there are also two further monitoring instruments: the X-Ray Monitor (JEM-X) and the Optical Monitoring Camera (OMC).
With its high angular resolution (12 min), the imager can provide a detailed map of gamma sources. At the same time, the spectrometer's high-energy resolution capabilities enable it to establish the spectrometry of these sources. The JEM-X and OMC are used to make correlations within the X-ray and visible domains respectively.