FeaturesWorks for HeadPhone-Look CablesBoth speedometer and 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 jack" look connection tips. E.g. many bike models by Sunny, PooBoo, L-Now, Snode, Exerpeutic, Pleny, Yosuda, Ativafit, Faafuu - 95% of Amazon brands as well as domestic brandsOptional Heart Rate Monitoring FeatureAn optional feature that works with bikes with pulse sensors (usually 2 x metal pieces on handle bars). Re-wiring MIGHT be required for some perticular models.2 x AAA Batteries Not Included - RequiredBatteries are NOT included.SpecificationModel: ZT-JP040Counting range: 9999 (pcs)Input signal voltage: 1.5V (V)Specification: SM connectorSize: 147 x 124mmLCD Size: 50 x 23mmTips:Please allow 1-3cm error of measurement.Photo color might be a little different from the actual product due to color display of different monitors. Product Includes: 1x Monitor Speedometer Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.