DESC: Digital Filter Technology for Accurate Measurement:The Digital Filter Technology uses a sensor to detect and isolate only the essential pulse oscillation. It helps eliminate other noise factors, leading to quick and reliable measurement capability. This also helps avoid over-tightening of the cuff on the wrist.Body Movement Indicator Detects Arm Motion:The monitor lights up if you are moving during a reading, alerting you to the fact that your reading will not proceed unless you stop moving.