The Fitbit ACE 3 Kids Activity Fitness Tracker is a multicolored activity tracker made of silicone and designed for indoor and outdoor use. It measures heart rate, time, distance, and calories in imperial units and has a battery life of up to 8 days. The device is compatible with iOS and Android operating systems and features Bluetooth connectivity, GPS, and ambient light sensors. It is ideal for gym and training, weight lifting, swimming, yoga, and running and jogging. The device is 1.4 inches long, 5 inches high, and 0.0425 lbs in weight.