The DLS-45 features a Two-Step Voltage Jack which allows switching from a long-term float voltage of 13.6vdc to 14.2vdc for rapid charging by simply inserting the dual voltage plug (included) into the jack. The DLS-45 is also available with an IQ smart-controller already integrated into the unit which converts the charger into a 3-stage "smart" charger, increasing the performance of your DLS-45.