High pressure, low temperature, high magnetic field data obtained on high quality single crystals of NiS2, to clarify the nature of the pressure induced metal-insulator transition and to map out key parts of the electronic Fermi surface in the high pressure metallic state. Resistivity measurements under pressure were carried out at the Cavendish Laboratory, Cambridge, and tank circuit oscillator measurements were carried out at NHMFL Tallahassee. The Fermi surface calculations were performed using Wien2k and plotted using Xcrysden. Details of the methods and analysis methods are published in the Scientific Reports article with the same name.