TCI offers this Pressure Sensor that is designed for use with their Shift Boss Transmission Programmer. For performance GM 4L60E, 4L65E, 4L70E, 4L80E and 4L85E applications, the TCI Shift Boss will ensure your desired shift firmness while monitoring important drivetrain functions, including line pressure and temperature. This optional item is sold separately from the Shift Boss Transmission programmers.