Question: What is a "Float" charger? What "Float" voltage do we recommend? Answer: A float charger is sometimes called a "smart" charger. This type of charger has extra electronics built in so that the charger continually monitors the battery's voltage. When the voltage drops below a designated setting (the float "voltage"), the charger automatically turns itself on. It charges the battery until it comes back up to the proper voltage, and then shuts itself off... or nearly off. Some keep a few milli-amps of current flowing to the battery, which may be a problem if this current is too high. These chargers are used in stationary, emergency back-up power, emergency lighting, etc., type applications. OUR RECOMMENDED FLOAT VOLTAGE IS: 13.8 V for Gel and Absorbed SRG