This is the right atrio ventricular valve, also known as the tricuspid valve. Now, what the function of this valve is the following. During relaxation, valve number one is actually open and that's to make sure that the blood flows from the right atrium and into our right ventricle. But when this right ventricle is filled with blood, it needs to contract. And to prevent the back flow of blood from the right ventricle back to the right atrium, this valve actually closes as a result of pressure and that ventricle contracts and it pumps blood from the right ventricle and into the pulmonary circulation via these pulmonary arteries that move DEOX data blood into the left and the right lung. So this is the right atriove ventricular valve, valve number one.