The phosphate comes off here without the use of a co-enzyme. The reason why is because GDP could steal it by piggybacking on the energy that was released when the co-A popped off. So now we've got succinate, 4 carbon molecule. The succinate goes to fumarate. And here we actually don't use NAD+, to steal hydrogens and electrons. We use FAD, see there's no plus there. Flavonide adenine dinucleotide (FAD) This is going to be B2? Yes. Perfect.