Adjustable RPM Shift Light. Affordable performance: Set shift point without a tachometer! Dial in desired shift point light flashes on. At pre-set RPM, light will flash on. Range is 3- 12,000 (X200) RPM. No racing tach needed! Does not require separately purchased RPM modules! Some applications may need a late-model tach adapter. Product Features:Stand Alone Adjustable Knob Model3,000 to 12,000 RPM Range200 RPM Increments1.5-in. Diameter5-in. Long