Argo Battery Isolating Diode Splitter - 120A - 2 Outputs

 Argo Diode Battery Isolators

Diode battery isolators allow simultaneous charging of two or more batteries from one alternator, without connecting the batteries together.
Discharging the accessory battery for example will not result in also discharging the starter battery.
Low voltage drop due to the use of high efficiency Schottky diodes.