The REDARC Smart Start SBI212 is a battery isolator used as a solenoid priority system to protect the start battery from excessive discharge while the auxiliary battery is supplying non-essential loads. It provides 12-volt DC with the incorporation of 200A of continuous ratings. The SBI212 is designed for extremely heavy-duty operations. It's primarily used in commercial vehicle dual battery systems. It incorporates electronic components to prevent the solenoid from generating high voltage transients. It is better than a diode battery isolator due to the voltage drop associated with diode type isolation. Its low standby current draw and sophisticated fault detection and LED indication of operation warns the user of faults including over-voltage, voltage drop, and excessive current draw conditions. The Smart Start SBI battery isolator is a safe way to top-up your secondary battery in your dual battery system with its power saving technology for the ultimate performance.