Traxxas Auto-Detectable Voltage Sensor use with the TQi Telemetry Expander(6550)

Traxxas Auto-Detectable Voltage Sensor, only for use with the TQi Telemetry Expander (TRA6550) The auto-detectable voltage sensor plugs into the optional TQi™ Telemetry Expander to provide real-time voltage data while you drive. Real-time telemetry requires a TQi radio with Traxxas Link™ Wireless Module and the free Traxxas Link app for your mobile device.