MaySpare Dual Battery Isolator Kit 12V 140Amp Voltage Sensitive Relay VSR Double Battery Automatic Charger & Wiring Cable Kit

This seller makes a great product. All the hardware and wire necessary to install the dual power isolator. Good instructions. I ran the dual power isolator to a AGM power box in the passenger floor area of my Dodge Caravan. Wanted to be able to monitor the isolator and connected a voltage meter to monitor the main battery and auxiliary battery. The gauge of wire is right and everything is working great. I glad I bought this product.

Can I return just the isolator? Mine dosent work even my start up battery is at 13.8 volts already and still don’t charge my second battery. I dont want to disconecy the wirings. I just need to change the unit.

My 2017 subaru outback has a "smart" or variable alternator, and my initial test of this unit showed that the battery voltage constantly dropped under 12.5v while driving around town which caused this unit to do what it's supposed to do and cut power to the aux battery side. Obviously that wasn't going to work with a trailer and aux battery hooked up. The only way to get around the "smart" or variable alternator feature is to TURN ON YOUR PARKING OR DRIVING LIGHTS. This causes the ECU to "turn on" the alternator to provide a constant >14.0 volts to the battery the whole time the engine is running. If you turn your lights off, you'll see the alternator voltage drop to 12.5v or lower.

Installed easy and came with straight forward instructions. Does a really good job at keeping my secondary battery charged. It also has a relay to reverse the flow of power to your main battery, It works really good. Nice to know you can self jump start yourself.

Failed after two weeks. Had to buy another at an autozone on our road trip

Great kit I installed a second 100 amp Renogy AGM battery with an inverter and cigarette lighter and USB ports in the back of the canopy on my F150 4wd. Easy to wire, clear instructions.

Got this to add a secondary battery for my truck to charge tools while on the job site and run a few appliances. This worked great!

Just what I needed for keeping the two house batteries in my van charged. Cable was long enough to get from my starter battery to my house batteries at the back of my extended fullsize van. Smart isolator has performed flawlessly, even when I depleted my house batteries twice, and done numerous rough gravel roads. Solar gets lots of attention but this is WAY more useful.

Very pleased came with everything I needed to install a second battery in my kawaski teryx for running all my accessories

Works as advertised, plenty of wire for the installation. Fair deal

Work as described, aux. battery charge well since 2 years.

This is the first time I write a review for a product. I either don't write a review or give a bad review, but I do want to give a good review for this product. Not to mention the product itself, the accessories, connectors, and wires that come with it are far more expensive than the price. The products of such a merchant must be good. At present, I have tested the mains charging and engine charging on my RV and they are very easy to use.

Plan on adding on another battery to run my winch and stereo amplifier. There were very few places that had them , but they were very pricey. So I found it here at a reasonable price.