Packaging opened but item is unused. The Bontrager DuoTrap S Digital Sensor is a wireless bike computer designed for cycling enthusiasts. It provides accurate speed and cadence measurements using an accelerometer sensor, making it ideal for tracking your performance during workouts. The sensor is compatible with Trek bikes and offers both decimal and imperial measurement systems. Powered by batteries, this black plastic device is a must-have for cyclists looking to improve their training and reach their fitness goals.