The Panasonic EW3109W Automatic Arm Blood Pressure Monitor is the first portable arm unit in the industry. The easy-fit cuff, designed for comfort and to assure correct and accurate use, rolls around the slim baton-style monitor for portability. The large "Easy Read" LCD display gives you digital readings on inflation with memory capabilities that can capture up to 90 readings with an averaging feature allowing you to save and track readings over time. Panasonic's Digital Filter Technology assures accurate measurement of blood pressure readings every time with sensors that isolate and detect only essential pulse oscillation, thereby eliminating noise factors which can cause unreliable measurements. The Flashing Warning System alerts you if your blood pressure reading is high or hypertensive. And with only one-touch of the start button, the unit auto-inflates and makes it not only accurate but extremely easy to use. This blood pressure monitor also comes with a carrying pouch and 4 AA batteries for in the box power. An optional AC adaptor and extra-large cuff (fits up to 17") are available and sold separately. Call our 24-hour, toll-free hotline run by Panasonic at 1-800-338-0552, and if there is a problem, we will exchange the product hassle free! All blood pressure monitors include a 2-year limited warranty. You can always trust Panasonic healthy living products to help you monitor your physical health in the comfort of your own home. Their range of blood pressure monitors are among the most popular on the market because they're reliable, easy-to-use, and accurate.