So this is actually the final product or one of the final products in the non oxidative phase. Now what we want to do in the final step in the final process is we want to take the urethrase for phosphate produced in process three, and we want to take the second zyulose biphosphate that we still have left over from process one. Remember, we only use one of the two zelulose molecules that we produced in step one in process one. So we use this one right here and now we use the second one in this process four. Now the enzyme that catalyzed the process four is the same enzyme that we used here. And so it's no surprise that this same enzyme uses the same substrate molecule.