And so our sodium ions cannot actually move out or in to our cell. So at the same time, this membrane voltage will signal the voltage gated potassium channels to actually open up and become active. And now these potassium ions will basically move down their electrochemical gradient. So, because we have a high concentration of potassium inside, and because we have a negative charge on the outside, these positively charged potassium ions will move down their electrochemical gradient and to the outside of our cell. Now, the reason we call it repolarization period is because this period basically attempts to return our membrane potential back to its resting potential. And that's because the positive charge begins to decrease on the inside as the positively charged potassium leave the inside and travel to the outside.