The Chuck Adaptor is inserted into the chuck of your drill. The Chuck Adaptor, the Shaft and the Male Pipe Fitting are all solidly attached together, and rotate with the drill. The Shaft Bearings allow the Shaft to turn freely. A hose is attached to the Hose Fitting. When the water is turned on and the valve is opened, water runs through the valve and into the Hydrodrill body. The Shaft Seals keep the water from leaking out.