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KeyLine Chargers

Dual Battery Isolator 12V | Automatic Battery Disconnect Switch 12V 140 Amp Voltage Sensitive Relay (VSR) | Car Battery Charger Switch Also for ATV, Boats, RV's, Off-Road Vehicles, by KeyLine Chargers

    • Based on 1,567 reviews
Condition: New
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$79.87 Why this price?

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Availability: In Stock.
Fulfilled by Amazon
Arrives Thursday, Feb 27
Order within 50 minutes
Available payment plans shown during checkout

Size: 140 AMP Isolator


Features

  • ZERO VOLTAGE DROP: Forget the traditional diode relays and so-called "solid state" devices that can rob you of almost 2 amps of output power! The Keyline Dual Battery Isolator is the only unit designed with cutting edge programming to deliver optimum performance - with ZERO sacrifice. This compact battery isolator was built ultra-small (2.6" x 2.6" x 2") to fit almost anywhere! A perfect fit under the hood to get close to your dual batteries.
  • VOLTAGE SENSITIVE RELAY: The KeyLine Automatic 140 Amp Dual Battery Isolator is all you need to charge Two Battery Systems. Voltage Sensitive Relay (VSR) cuts in at 13.3 volts and cuts out at 12.8 volts to ensure your primary battery is always charged and ready to start your vehicle. It's like having two separate power sources for each battery while only having one alternator!
  • RUGGED DURABILITY: Unlike other isolators on the market, the KeyLine Automatic 140 Amp Dual Battery Isolator is IP65 Certified. This International Protection rating means that your KeyLine isolator is safe for use even for your off-road needs in dusty, wet and unexpected extreme weather environments. Great for extreme vibration applications as well.
  • EASY-TO-USE: The 140 Amp Dual Battery Smart Isolator comes with mounting plate and hardware. Does not include installation wires. Easy-to-follow directions for the most novice DIYer. What could be easier? **If you need installation wiring, see Dual Battery Kit or ATV/UTV Kit.
  • BUY WITH CONFIDENCE: Every 140 Amp Dual Battery Isolator is backed by an industry leading 12-month warranty. If you are not 100% satisfied with your purchase, simply take advantage of the No Questions Asked, 30-Day Money Back Guarantee!!

Operation Mode: Automatic


Current Rating: 140 Amps


Operating Voltage: 12 Volts


Contact Type: Normally Open


Connector Type: Crimp


Brand: KeyLine Chargers


Item dimensions L x W x H: 1.97 x 1.97 x 1.97 inches


Mounting Type: Plug-In Mount


Actuator Type: Rotary


International Protection Rating: IP65


Operation Mode: ‎Automatic


Current Rating: ‎140 Amps


Operating Voltage: ‎12 Volts


Contact Type: ‎Normally Open


Connector Type: ‎Crimp


Brand: ‎KeyLine Chargers


Item dimensions L x W x H: ‎1.97 x 1.97 x 1.97 inches


Mounting Type: ‎Plug-In Mount


Actuator Type: ‎Rotary


International Protection Rating: ‎IP65


Connectivity Protocol: ‎X-10


Wattage: ‎1680 watts


Unit Count: ‎1.0 Count


Number of Items: ‎1


Manufacturer: ‎KeyLine Chargers


UPC: ‎640791978883


Model: ‎ISO-Variation


Item Weight: ‎9.6 ounces


Product Dimensions: ‎1.97 x 1.97 x 1.97 inches


Item model number: ‎ISO-Variation


Is Discontinued By Manufacturer: ‎No


Exterior: ‎PVC Matte Black


Manufacturer Part Number: ‎Iso-Pro140


Date First Available: April 28, 2015


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Thursday, Feb 27

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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  • Financing through Apple Pay
Leasing options through Acima may also be available during checkout.

Learn more about financing & leasing here.

Similar Products

Top Amazon Reviews

    • Works great.
Size: 140 AMP Kit
Easy install
Reviewed in the United States on June 9, 2024 by clarence elam
    • Great isolator. Works great in 2016 Polaris Ranger 900-5 Crew.
Size: 140 AMP ATV/RV
Ive had this in my Polaris ranger 2016 900-5 crew, for about 8 months. I have 2, 1200 Odyssey batteries installed. This thing works like a champ. It passes the charge to the battery that needs it the most. I tax my system more than most people ever will, and this isolator does more than I need it to. You have to understand your setup and how it all charges or you wont understand how this thing works. I have 2, 54in curved 4D light bars, and 2, 50in curved 4D light bars, along with 2, 7in light bars, and in cab, mulit color lights. I can run all night on my setup. I can hunt 3,000+ acres, for over 8 hours without any issues. I can hear the isolator clicking back and forth, and I can watch my voltage move around. I never drop under 10 volts, on a full load, and that is after all night of hunting. It would of been nice to have longer and better neg and pos. cables, but because of all the other work done to the Ranger, I did have better cable laying around. Others will not have the same luck. So a tip to the seller. Just give the better, longer cables. It wont cost you that much more, and honestly even if it does, I would of paid to have the better cables. Outside of that, I didn't buy this for the cables. I needed the isolator, and it is great quality, and works flawlessly. ... show more
Reviewed in the United States on June 19, 2017 by Brantley Hickerson
    • Does the job at 1/3 the cost
Size: 140 AMP Isolator
Had a Redarc that failed just when I needed it most (in the middle of nowhere in a foreign country with no expedite delivery) This unit does same job, 1/3rd of cost so you can carry a spare and still save some money. Easy to install and functions as it supposed to so far.
Reviewed in the United States on December 24, 2023 by Calin
    • Don’t plan on using their red cable.
Size: 140 AMP Kit
Review Image by 55reasons 55reasons
If the power cable that came with the kit wasn’t so cheap I would give it 5 stars. I updated the batteries behind the seat of my 84 Toyota pickup rock crawler with this kit. It’s a good quality product until you get to the red cable they give you to hook up the batteries. It’s not nickel plated solid core, and it has very few strands. The insulation on the wire is more like hard plastic than a soft rubber. It’s a PITA to strip the insulation off the cable, and it just feels, like, really.....Chinese in origin. I’ve been doing things like this for over 30 years and this the first cable that was so unpleasant to work with that the whole time I just kept saying things like “Where did they get this wire?”, and “This is the worst wire I’ve ever seen!”..... Aside from that, everything else in the kit was good. I also think the mounting “kit” was cheap though. I didn’t use anything from the little duplicate bag. The heat shrink is cheap, (not extra thick) the screws are not stainless steel, etc. But if you ignore all the “accessories”, the unit itself is fantastic. ... show more
Reviewed in the United States on May 1, 2021 by 55reasons 55reasons
    • It works
Size: 300 AMP Kit
Installed it 4 months ago as a bank up battery for my system and aux lights. Works as it should and works flawlessly.
Reviewed in the United States on May 29, 2024 by Rojo
    • The best solution for battery isolation
Size: 140 AMP Isolator
I was looking for a good quality relay to be used in my Chevy truck to isolate an auxiliary battery. My OEM relay failed, but it was 30 years old. The auxiliary battery is used as one of two batteries for my pickup camper - one is in the engine compartment and the other in the camper. I tried three different isolation relays, two of which looked pretty good. The Stinger SGP32 was the best, since it drew the least amount of current when activated. But then further searching brought me to this relay, which works with a clever design using voltage rather than just an ignition circuit. I ordered one of these and the Jaycorp Smart Battery Isolator, which also looked good. When I received them from amazon I found them to be almost identical in design, and upon bench testing they both worked perfectly. I ended up keeping the Keyline product and returning the Jaycorp relay, but only because I liked the small red LED a bit better than the bright blue LED on the Jaycorp relay. Either relay looks to be a great solution for battery isolation. If this Keyline product proves reliable, I'll be a very happy camper! Update 8/3/21: This isolator has worked perfectly since I installed it. A 5 star product! ... show more
Reviewed in the United States on September 4, 2019 by Ray R. Kawal
    • Bad
Size: 140 AMP Isolator
I bought this for my promaster which i live out of, first, the sides don’t have holes for wires to come out, backplate doesn’t fit when wires are connected. Also it doesn’t work with my lithium batteries, either defective or just got getting high enough voltage to charge it. Final note is that the red light telling me it’s on would still be on after I’ve disconnected the starter battery, meaning it might be draining my house batteries. In the end I can’t return it due to having to cut a hole in the side to even test it, will be going with dc-dc charger from a more reliable company EDIT: THEY MADE IT RIGHT WITH A REFUND ... show more
Reviewed in the United States on October 16, 2023 by Elijah

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