The MFSU is a third-tier storage device in the IndustrialCraft mod. It stores 10,000,000 EU of energy, but is the costliest to make, requiring 10 diamonds.
It outputs HV, so to use most machines with it, they require Transformer Upgrades or step-down transformers like the MV-Transformer and the LV-Transformer wired in series to prevent the explosion of your setup.
It has 5 input faces, just like the MFE, and 1 output face which it can send up to 512 EU/t.
It is recommended to use the MFSU when storing energy from a large output generation setup, like a Nuclear Reactor.
It is also possible when using Glass-Fibre Cable to chain them together to make a mass storage system.
The MFSU requires an MFE, an Advanced Circuit, an Advanced Machine Block, and 6x Lapotron Crystals to make.