Don't expect a top-shelf HRM for this price. The menus are confusing and not at all intuitive, and the instruction manual was likely written by a 9-year-old chinese boy. If you press/hold both bottom buttons at the same time, it goes into a master reset, erasing all the settings for time, date, target heart rate and alarm... Between my brother, wife and myself, we have three of these, they all operate similarly. They are inexpensive, but they work once you learn to live with the quirks. Make sure you hang on to the manual- poorly written as it may be, you'll never figure out the settings without it.