This product has been replaced by MB3685. Click here for the replacement
A voltage sensitive relay (VSR) is the best way to ensure you can always get your dual-battery vehicle started. If the radio stops working that’s one thing, but if you’re stranded because your car cannot start because you ran your fridge for too long, that’s potentially a life and death scenario. It allows two batteries to be charged from your alternator. Once your main starter battery is sufficiently charged, it will begin charging the second battery too.
• Protects your starter battery
• Automatic operation
• Ideal for 4WD, marine, and more
• Cut-In Voltage: 13.3VDC
• Cut-Out Voltage: 12.8VDC
