cylinders connected in parallel

At this picture we see cylinders connected parallel , we use this system to move poth cylinders at the same time when the oil reach the lever , and we move the lever to the first state ( from the pump to the cylinder and then the oil return to the tank ) whech shown at the up square , the oil start to flow to the cylinders then the pressure cause to push the pistons , by this movement we can move the load up or down , the oil which existing at the other side of the cylinder start to flow and goes back to the tank , then we change the lever to the state which show in the down square of the lever picture which allow to the oil which existing in the left side of the cylinder to go back to the tank and the oil flow to reach the other side ( right side ) we now move the load down and it return to the tank .