We've got our pesticide in the container in the right mixture. We're going to compress the air. And that's done by pumping this handle up and down. Each time you come up it charges with air and when you push it down it puts it into the tank without releasing it back. There's a one way valve at the bottom of that pump assembly that allows the air to go in but not to come out. Now, when you reach the maximum pressure. We talked about the pressure release valve a while ago. When you reach the maximum pressure that this pressure release valve will allow or get close to it, this red cap starts to move out and you start seeing a yellow band behind there. That means that you're reaching the maximum pressure that you need to be putting in this tank. If you keep pumping, each time you pump, it'll just release what you put in there. But you don't want it to get to that kind of pressure. You want to, just as soon as you start seeing the yellow, you need to back off and do some spraying to relieve the pressure inside the tank. Because, you know having the tank highly pressurized is not the best thing. You just want it pressurized enough so that you're producing enough pressure to spray with. And once you get a uniform spray application going well that's all you need.