Features: There are 2 types, with as/sm connection, chhose according to your needs. Both the speedometer and pulse tracking are provided by a 3.5mm female socket on the back of the monitor. Suitable for stationary bikes with "head phone jack" connection ends. E.g. solar bikes, PooBoo, l-now, knot s, etc.2 x AAA batteries not included-required: batteries are not included for safety. Large LCD display, the data is clear at a glance, which is convenient to read. Specification: Material: ABS Connector: as/sm (optional) Input Voltage: 1.5V Package Includes: 1x SpeedometerNote: Please allow 1-3cm error due to manual measurement. Pls make sure you don't mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item.