And the reason we have these identical sequences is because we have four of these identical polypeptide chains that create this tetrameric structure. And so what happens is one of the functions of the selectivity filter, this sequence of five amino acids, is that they're oriented in such a way so that the Carbonal oxygen atoms, these atoms show the red of these residues. These amino acids basically orient themselves in such a way as to form stabilizing directions between the partially negative charges of the oxygen and the false positive charges on those potassium ions. So these interactions shown in green, and those interactions are overall more stabilizing than interaction between the water and the potassium. So even though we have to input a certain amount of energy for this potassium to actually move into this restricted area and break that salvation cage, we form more stabilizing bonds. And when these bonds are formed, energy is released.