I'm selling it because I don't use it The following is from the site: Advanced Fitness Tracking Fitbit Charge 4 features built-in GPS to provide accurate distance measurement while running or cycling, allowing you to track your activity in greater detail. [Heart rate and sleep monitoring] 24/7 heart rate tracking helps you keep track of your heart rate variability, while the sleep score helps you analyze your sleep quality and identify areas for improvement. [Long-lasting battery] With a battery life of up to 2days, you don't need to charge it frequently, so you can use it with confidence during your daily life and exercise. - Brand: Fitbit - Model: Charge 4 - Color: Black - GPS function: Built-in GPS - Heart rate tracking: 24/7 heart rate tracking - Battery life: up to 2 days - Sleep Score: Sleep score function - Fitbit Pay: Fitbit Pay feature This is a 新品 item. Please be aware of this before purchasing.