LVD - 12 Volt Low Voltage Disconnect Switch:

An LVD (Low Voltage Disconnect) switch protects your battery from over-discharge and can protect loads from running at voltages below rated input levels. The LVD will constantly monitor your battery and disconnect the attached DC load(s) if voltage drops below an unsafe level. Also, in applications where loads (such as pumps) are connected directly to solar modules, the LVD can be wired directly to a solar module to switch the load on and off relative to the voltage output level of the solar module. Epoxy encapsulated and ready for marine or tropical environments. This 12 volt LVD has an adjustable disconnect/reconnect feature.