Brass Thread Reducer/Adapter/Insert 12X1.25 Od 8X1.25 Id For Shift Knob Knobs for Jeep Wrangler Made from solid brass. This reducer is perfect for most aftermarket bubble knobs Inside diameter is 8x1.25 (fits most honda's) Outside diameter is 12x1.25. Total length is 25mm. Installs in seconds!.