Large LCD display for easy reading of speed, distance and riding time. Compact wireless and waterproof design, lightweight and durable. Measures speed, distance and riding time to support serious cyclists and fitness enthusiasts. Day and night backlight with green and white illumination for clear visibility in any lighting. A slight rattle from the device is normal and caused by the wireless automatic function. Sleek, practical design. Functions as a bicycle speedometer and odometer, providing speed, distance and riding time data. Wide compatibility: suitable for road, mountain, folding and standard bicycles. Use scenarios: - Road riding and commuting: monitor speed, distance and ride time at a glance. - Mountain biking: track speed and distance in rugged conditions with reliable waterproofing. - Fitness training on any bike: keep progress for daily workouts and training rides.