This cuff blood pressure monitor was named The Best by the Hammacher Schlemmer Institute because it provided the most accurate readings, was the easiest to use, and offered the most amount of additional features. Each monitor’s systolic and diastolic measurements were compared to readings taken by a medical grade blood pressure monitor. The Best model’s results were the most accurate, only deviating by an average of 6.5 mmHg for systolic and 4.30 mmHg for diastolic. Also rated as the easiest model to use, The Best unit had clear instructions, an easy-to-read screen, simple operation, and color-coded indicators that allow you to quickly determine where results fall on the American Heart Association’s guidelines. Its list of superior features include irregular heart beat detection and a pulse rate indicator. It also pairs with a smartphone for tracking readings on an app and stores up to 200 readings for two people. Includes four AAA batteries. Can be used on either arm. Fits arms 8 3/4"-16 1/2" in circumference.