Do you have a need for speed? Or at least a need to know your speed? Well, we have a quick and easy solution to make your old transmission communicate with an electronic speedometer. Old school transmissions used a cable-drive speedometer, and many aftermarket gauge companies feature electric speedometers. This Auto Meter Speedo Sender features 7/8-18 threads, and threads into most GM and Chrysler transmissions providing an electric signal to the speedometer. An electric speedometer sender is a small part but it certainly relieves a lot of hot rodder headaches!