Function description of magnetic control car instrument, spinning bike instrument: 1. TIME: Press the MODE button to display the time. This value represents the elapsed time from the start of the movement. 2. SPEED: Press the MODE button to display the speed. This value represents the current speed of movement. 3. DISTANCE: Press the MODE button to display the distance. This value represents the total distance traveled during the movement. 4. CALORIE: Press the MODE button to display the calories. This value represents the energy burned during the activity. Works with Headphone-Look Cables: Both speedometer and pulse tracking connections are through 3.5 mm female jacks on the back of the monitor. Adapters may be needed if the device has female jacks (rare cases). Compatible with Most Indoor Exercise Bikes: Designed for stationary bikes with "headphone" style connection tips. Fits many models from brands such as Sunny, L-Now, Pleny, Faafuu – compatible with approximately 95% of home and commercial indoor bikes. Heart Rate Monitoring Feature: Works with bikes equipped with pulse sensors, typically two metal contact points on the handlebars. Rewiring may be required for certain models. 2 x AAA Batteries Not Included – Required: Batteries are not included. Product size: 108 x 163 mm LCD size: 48 x 23 mm Color: White Material: Plastic Package Contents: 1 x Monitor Speedometer with Heart Rate Function Only the above package content is included; other products are not included. Note: Lighting and different display settings may cause slight color variations between the item and the image. Measurement error allowance is +/- 1-3 cm.