ACCURATE HEART RATE MONITOR - Optical heart rate technology to give you accurate heart rate, calories burned, distance, speed, pace. BLE4.0 & ANT+ DUAL MODES- The HW702 supports both Bluetooth and ANT+ connection, works with most Bluetooth Smart and ANT+ enabled devices and equipment: watches, fitness equipment, smartphones, and tablets Breathable. IP67 WATERPROOF - The best choice for fitness lovers. It can be used for handwashing, household chores and in the rain. However, it is not recommended for swimming or bathing. COMFORTABLE ARMBAND - The breathable and light HW702 armband fits perfectly and comfortably around your arm, it is more comfortable than a chest strap. APPS COMPATIBLE - Works with most mainstream Smartphone Apps including Wahoo Fitness, Zwift, Runtastic, Runkeeper, UA Record, Endomondo, Peloton, Map My Run, Komoot and Nike Run Club, etc.