SE102 is an entry-level heart rate watch with basic heart rate measurement and calories burned features. With a simple tap on the lens of this product, you can change the readouts to display relevant information. The included chest belt transmitter is worn comfortably against the skin. The chest belt picks up the heart signals, and sends them wirelessly to the watch. The watch unit receives and shows heart rate signal. The upper and lower heart rate zone alarm can be programmed as a visual or vibrating alert.