DIGITAL, with timer and heater and standard basket. Stainless steel tank and cover. Ultrasonic cleaning occurs when ultra-high frequency sound waves (Hz) are passed through a cleaning solution creating cavitation, microscopic bubbles collapsing into themselves. This creates a high energy, vacuum effect which safely pulls debris, foreign particles and other contaminants from the surfaces being cleaned. With ultrasonic cleaning, both the exterior and the interior surfaces, including crevices, are thoroughly cleaned. Ultrasonic cleaning has been proven to be sixteen times more effective than manual methods. JSP® Ultrasonics feature stainless steel tanks. All units have a heater with a timer which allow you to pre-set the temperature and time for maximum cleaning results. 220-240 volts not recommended for use in the USA unless you have 220-240 volt power.