So this L shape structure contains the horizontal component that lies in the membrane of the mitochondria, the inner membrane. And we have a vertical component that extends into the matrix of the mitochondria, and the NADH actually binds onto this extension that lies in the matrix of the mitochondria. And along with the NADH, an H plus iron is also actually used. And we'll see why that H plus ion is needed in just a moment. And so, in the process, we ultimately oxidize the NADH back into NAD plus. And those two electrons are extracted by a group known as FMM, and the FMN stands for Flavin mononucleotide.