WhisperPower - WP-Modularer Batterie-Fernschalter,

The modular DC remote battery switch (the Switch) is an intelligent, high-current, magnetic interlocking contactor capable of handling continuous direct currents of up to 500 amps. The switch can be easily installed in the engine room or battery compartment, while being controlled from a more convenient location via a small, panel-mounted switch. The switch can also be controlled by a battery monitor or a lithium battery as discharge/overcharge protection, for example.