Works great! Used for about 6 months before getting different kind. I do have an old band attached to it but you can buy and attach any bands that are compatible with the Fitbit sense. EDA Scan app detects electrodermal activity which may indicate your body's response to stress and a built-in skin temperature sensor logs yours each night so you can see when it varies. Assess your heart for atrial fibrillation –a heart rhythm irregularity- and easily share results with your doctor (The Operating temperature: 14° to 113°F An on-wrist skin temperature sensor tracks yours each night so you can see how it varies. You can also see your nightly blood oxygen levels at a glance with our collection of clock faces.Radio transceiver: Bluetooth 5.0.Operating temperature: -10° to 45° C High & low heart rate notifications alert you if yours seems above or below your average.Battery lasts 6 plus days plus, fast charging gives you a full day's charge in just 12 minutes (Varies with use and other factors; up to 12 hours with continuous GPS).Use built-in GPS during runs, hikes, rides and more to see pace & distance without your phone and use the built-in mic and speaker to take Bluetooth calls hands-free when your phone is nearby (Requires more frequent charging).