Function description of magnetic control car instrument, spinning bike instrument:1. TIME: Press the MODE button to display the time. This value represents the time from the start of the movement to .2. SPEED: Press the MODE key to display the speed. This value represents the speed of the current movement.3. DISTANCE: Press the MODE key to display the distance. This value represents the distance from the start to of the movement.4. CALORIE: Press the MODE button to display the calories. This value represents the energy burned from the start to .Works for HeadPhoneLook Cables]Both speedometer & pulse trakcing connection are through 3.5 mm female jacks on the back the monitor adapters (NOT INCLUDED) might be needed if the device also happen to have FEMALE jacks (rare cases).[Compatible with Most Indoor Exercise Bikes] for Stationary Bikes with "head phone " look connection tips. E.g. many bike models by Sunny, , LNow, , , Pleny, , , Faafuu 95% of Amazon as well as domestic [Heart Rate Monitoring Feature]that works with bikes with pulse sensors (usually 2 x metal pieces on handle bars). Rewiring MIGHT be required for some perticular models.[2 x AAA Batteries Not Included Required]Batteries are NOT included.Product size: 108x163mmLCD size: 48x23mmColour: whiteMaterial: plasticPackage Contents:1 * Monitor Speedometer W/ Heart RateOnly the above package content, other products are not included.Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/ 13cm.