2.5 AMP Rapid Lithium Charger OnlyThis 2.5 amp hour rapid charger is designed for Vexilar Lithium batteries ONLY and works best when connected directly to the battery terminals using the supplied Gator clips. As the RAPID name implies, it is the best choice for many of the higher amp 12-volt batteries that you need to get a charge into quickly. The easy-to-understand charging lights make charging a snap. Green light signals to power or charge completely. The red light tells you the battery is charging. Blinking red is a warning that the battery is too cold to charge or the terminals are reversed. Special charging instructions to get the most out of your V-420L Rapid Charger can be found at www.vexilar.com.