Function of magnetic control car instrument, spinning bike instrument: 1. TIME: Press the MODE button to display the time. This value represents the elapsed time of the workout. 2. SPEED: Press the MODE button to display the speed. This value represents the current speed of the movement. 3. DISTANCE: Press the MODE button to display the distance. This value represents the total distance covered during the workout. 4. CALORIE: Press the MODE button to display the calories. This value represents the estimated energy burned during the workout. 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 – for stationary bikes with "head phone" style connection tips. Fits many bike models by Sunny, L-Now, Pleny, Faafuu, and others. Compatible with 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 for operation. Product dimensions: 108x163mm LCD size: 48x23mm Color: white Material: plastic Package contents: 1 x Monitor Speedometer with Heart Rate Function Only the items listed above are included; other products are not included. Note: Lighting and different display settings may cause slight color variations between the product image and the actual item. Measurement error allowance is +/- 1-3cm.