Capacity mah75 materialabs tpu silicone connectionbluetooth30 bluetooth40 typesmart bracelet featuressleep tracker creative water resistant water proof wearable sports health care multifunction distance tracking long standby pedometers alarm clock find my device modeld21 sensorfinger sensor heart rate sensor accelerometer proximity sensor gravity sensor supported operation systemiphone android ios screen typedisplay technologyoled stand by timeh120 150