The technical bits:

EFB (enhanced flooded battery) batteries are an enhanced version of standard wet-flooded technology. The primary benefits of EFB technology are improved charge acceptance and greater cyclic durability when operating in a reduced state of charge. As an approximation, EFB batteries will provide 85,000 engine starts, compared to 30,000 starts from standard flooded product.

The Smartpass 120S:

• is a 120A Power Management Solution which distributes, controls and maximises the available energy from your alternator to power service batteries and consumers.
• handles all 12V batteries between 28-800Ah
• the Battery Guard function ensures that critical equipment such as radio, emergency lights and navigation systems always have power and take priority when the voltage on the service battery is low disconnecting non-critical consumers
• the unit’s Battery Guard will protect your service battery from total discharge and built in over temperature protection reduces charge current before the battery temperature gets too high
• is compatible with the D250SA and D250SE 20A on board chargers

So we have alternator input on the top left, output to the Service Battery top right, and the “Output Consumers” bottom right – for those non-critical consumers of power.

This system combines with the D250SE when you wish to add solar charging to your setup.

Both the Smartpass and the D250SE can be used with AGL and Lithium batteries – should you wish to go that route.

The Smartpass 120s and D250SE can be tidily mounted together. BlackSheep have released an adapter plate to facilitate this. This is screwed to the original mounting points, and alows these devices to be coupled as intended by the manufacturer.