The GTS 4 uses industry-leading dual-band circularly-polarized GPS antenna technology, similar to that used in the aircraft and automotive fields, allowing for stronger positioning that is 99% as accurate as top handheld GPS locators. It's time to see the bigger picture of your health and fitness. Immerse yourself in the ultra-large 1.75" AMOLED display and view the data that matters to your wellness journey in pristine HD clarity. Enjoy highly accurate 24-hour monitoring of heart rate, blood-oxygen saturation, and stress levels. The watch can also detect your breathing rate and quickly measure these four important health metrics with one easy tap.