The Dedenbear ST1 is a single stage timer that can be used to activate a device such as a shifter, throttle stop, nitrous solenoid, or timing retard based on time rather than RPM. The Shift Timer works particularly well in cars that have 'loose' converters. The engine in a car with a 'loose' converter tends to run at a fixed RPM until the converter locks up and stops slipping. Since the engine runs in a narrow RPM band near the intended shift point for a large portion of the run, the actual shift point can vary widely. The ST1 will allow the car to shift at a precise point during a run and the engine RPM doesn't matter.