Self contained. No adapters, activation modules, "pills", etc. are needed ! Simply turn the two rotary RPM switches for the desired setting, and select the cylinder setting to match your vehicle, cycle the power and the new settings are stored in memory. For 1 (coil-on-plug), 2, 3, 4, 5, 6 or 8 cylinder engines. Settings can be changed instantly with a small adjusting tool. High strength aluminum housings available in a variety of anodized colors.