And this wall that separates these two ventricles is known as our interventricular septum, which is the wall between the right and the left ventricle. So within this wall we have this bundle of his, which is basically a conduction channel that begins at the AV node and it travels through this wall separating our two ventricles. Now as it travels, as it moves, the bundle of his then splits into two different branches. We have the left bundle and the right bundle. And these continue moving within the interventricular septum and eventually also begin to split into very tiny extensions, very tiny fibers we call the perkinji fibers. And these PerkinsI fibers are found between the endocardium and the myocardium of our heart.