Traxxas 1/10 E-Revo Brushless RPM, TEMPERATURE & VOLTAGE TELEMETRY SENSORS These Telemetry Sensors Are To Be Used With The Traxxas TQi Radio System With The iPhone Docking Base Temperature &amp; Voltage Telemetry Sensor Short (Part # 6523) Plug Grey Plug Into V/T Slot On Receiver (Traxxas # 6518) Red Plug Will Be Used To Plug In The Power Tap From The ESC NOTE: If You Do Not Have A Power Tap On Your ESC, You Will Need To Order The Traxxas Power Tap, Part # 6541 (We Do Not Carry This Power Tap) About 7.5" Long (190mm) Temperature Telemetry Sensor Mou Includes: Sensor - Temperature/Voltage Short (Part # 6523) RPM Sensor, Short 3x4mm BCS (2) (Part # 6522) Telemetry Trigger Magnet Holders/Spur Gear (Part # 6538) Temperature Sensor Mount (Part # 6535) Part number(s) included (in factory packaging): 6523 6522 6538 6535