The water is forced through an orifice that has a small diameter orifice, anywhere from 0.004" to 0.045" depending upon the application. These orifices are made of extremely hard material, such as diamond, sapphire or ruby. This step converts the water stream from a high pressure stream to a high velocity stream. At this point the water is moving in excess of 2200 miles per hour (3657 kilometers per hour).