Ultrasonic cleaning uses cavitation bubbles induced by high-frequency pressure (sound) waves to agitate the liquid. The agitation produces high forces on stains adhering to metals, plastics, glass, rubber, and ceramics. This action also penetrates blind holes, cracks, and recesses. The intention is to thoroughly remove all traces of stains adhering or embedded onto solid surfaces. Water or solvents can be used, depending on the type of stains and the workpiece. Stains can include dust, dirt, oil, pigments, rust, grease and so on. Ultrasonic cleaning can be used for a wide range of workpiece shapes, sizes, and materials, and not require the part to be disassembled prior to cleaning. Professional ultrasonic cleaners are ideal for cleaning jewelry, eyeglasses, watches, metal tools, etc.