This Voltage Sensitive Switch (VSS) automatically senses connected battery bank voltages and provides optimal, efficient charging of the second bank. The VSS allows for the independent battery banks to be combined or isolated based on the presence of a charging source (such as an engine alternator or battery charger), while also offering remotely activated, high current, emergency parallel connection. Designed and constructed for longevity in the marine environment with tinned copper conductors, stainless steel nuts, and high temperature, fibre reinforced plastics. The units are ignition protected, provide On/Off switching operation, and may be recessed or surface mounted. The 720-MDVSO features digital circuitry and optical sensor positioning that automatically senses and adjusts for either 12V or 24V input, is extremely accurate, and offers low power consumption.Digital enhancements: Up to 67% reduction in stand-by current draw Multi voltage - auto selects between 12V and 24V DC operation (both battery banks must be either 12 volt, or both 24 volt) Only one SKU required, instead of separate 12/24 volt versions Increased accuracy of voltage measurement through digital circuitry Lowered cut in voltage from 13.7V to 13.3V (26.6V for 24V) to suit low output alternators, and high temperature environments