--- product_id: 322654187 title: "Dual Battery Isolator 12V | Automatic Battery Disconnect Switch 12V 140 Amp Voltage Sensitive Relay (VSR) | Car Battery Switch Also for ATV, Boats, RV's, Off-Road Vehicles,, Black" brand: "keyline chargers" price: "€ 98.55" currency: EUR in_stock: true category: "Key Line Chargers" url: https://www.desertcart.pt/products/322654187-dual-battery-isolator-12v-automatic-battery-disconnect-switch-12v-140 store_origin: PT region: Portugal --- # 140A Power Dual Battery IP65 Rated Dual Battery Isolator 12V | Automatic Battery Disconnect Switch 12V 140 Amp Voltage Sensitive Relay (VSR) | Car Battery Switch Also for ATV, Boats, RV's, Off-Road Vehicles,, Black **Brand:** keyline chargers **Price:** € 98.55 **Availability:** ✅ In Stock ## Summary > 🔌 Power Up Your Adventure with KeyLine! ## Quick Answers - **What is this?** Dual Battery Isolator 12V | Automatic Battery Disconnect Switch 12V 140 Amp Voltage Sensitive Relay (VSR) | Car Battery Switch Also for ATV, Boats, RV's, Off-Road Vehicles,, Black by keyline chargers - **How much does it cost?** € 98.55 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.pt](https://www.desertcart.pt/products/322654187-dual-battery-isolator-12v-automatic-battery-disconnect-switch-12v-140) ## Best For - keyline chargers enthusiasts ## Why This Product - Trusted keyline chargers brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Compact Design:** Fits seamlessly under the hood or in tight spaces. - • **Rugged & Reliable:** Built to withstand extreme conditions—dust, water, and vibration. - • **Zero Voltage Drop:** Experience uninterrupted power with zero sacrifice! - • **Confidence Guaranteed:** 12-month warranty and 30-day money-back promise! - • **Smart Voltage Sensitivity:** Automatically manages battery health for peak performance. ## Overview The KeyLine Chargers Dual Battery Isolator is a cutting-edge 12V automatic battery disconnect switch designed for optimal performance. With a robust 140 Amp capacity and a compact size, it ensures your primary battery remains charged while providing rugged durability for off-road and extreme weather conditions. Backed by a 12-month warranty and a 30-day money-back guarantee, this isolator is perfect for vehicles, ATVs, boats, and RVs. ## Description Your search for the best automatic battery isolator is over! KeyLine Chargers 140amp Battery Isolator is the best value on the market. Zero Voltage Drop. Won't rob precious power from your batteries and electrical system, unlike heat sinking competitors.Small Convenient Size. Only about 2 inches tall, wide & deep (2.6" x 2.6" x 2") the isolater fits just about anywhere!Fast & Easy Installation. Simple power wire IN, power wire OUT install. Comes with mounting plate/template.IP65 Weather & Strong Vibration Protection. Suitable for all off-road vehicles and weather exposed applications.Most Efficient Programming in the Business. Ensures your electrical system functions properly and batteries charge accurately.Voltage Sensitive Relay (VSR). Specially designed for ATV, UTV, boats, RV's, campers, 5th wheels, off road vehicles, Rhino, Polaris, Artic, Cat, Etc.Comes With Necessary Hardware & Mounting InstructionsDual Battery Voltage Sensitive Isolator User GuideFull 1 Year Warranty When it comes to SMART isolating... There is clear winner. The KeyLine Smart Battery Isolator works perfectly in all of your dual battery vehicles. When you're ready to go, don't get caught with a dead battery or left in the dust by inferior isolators! Do yourself a favor and buy one for a friend or a second vehicle that needs it - You'll thank us (and yourself) for good decision later. by KeyLine Chargers ## Features - Advanced Dual Battery Isolator 12V Kit – Designed for superior performance, this dual battery kit ensures efficient power distribution between two batteries without voltage drops. Unlike traditional battery isolator diodes, this automatic disconnect switch eliminates power loss while maintaining a seamless connection between your primary and auxiliary power sources. Compact at 2.6” x 2.6” x 2”, it’s perfect for under-hood installations or as part of a battery relocation kit. - Smart Voltage Sensitive Relay (VSR) for Optimal Charging – Featuring a 12V dual battery wiring kit, this system automatically activates at 13.3V and disengages at 12.8V, ensuring your starting battery remains fully charged. Whether you're installing a marine dual battery kit for your boat, a dual battery kit for truck applications, or need a battery isolator 12V kit for off-grid power, this setup prevents battery drain and guarantees reliable performance. - Built for Extreme Conditions & Rugged Durability – Engineered for off-road adventures, marine use, and daily driving, this dual battery isolator kit is IP65-rated for water, dust, and vibration resistance. Its solid-state design ensures durability, making it an excellent choice for automotive, RV, UTV, and marine battery isolator needs. Whether battling tough trails or navigating open waters, count on this dual battery wiring kit to provide uninterrupted power. - 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. - Trusted Performance with Warranty & Money-Back Guarantee – Every dual battery kit by KeyLine Chargers is backed by a 12-month industry-leading warranty. If you’re not 100% satisfied with your purchase, take advantage of our 30-day money-back guarantee—no questions asked! Drive with confidence knowing you have a premium battery isolator 12V kit keeping your power system running at full capacity. ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B00WTAFR84 | | Best Sellers Rank | #15,749 in Sporting Goods ( See Top 100 in Sporting Goods ) #4 in Boat Battery Chargers | | Item model number | ISO-Variation | | Manufacturer | KeyLine Chargers | | Product Dimensions | 5 x 5 x 5 cm; 272 g | ## Images ![Dual Battery Isolator 12V | Automatic Battery Disconnect Switch 12V 140 Amp Voltage Sensitive Relay (VSR) | Car Battery Switch Also for ATV, Boats, RV's, Off-Road Vehicles,, Black - Image 1](https://m.media-amazon.com/images/I/718YwOW-isL.jpg) ## Available Options This product comes in different **Size** options. ## Questions & Answers **Q: What gauge is the supplied wires?** A: The kit comes with 7 AWG wire, but wanted to comment on the customer who stated that it is not enough for a 20 foot run. At 140 amps, you would need 1/0 AWG wire, but with 95% of the applications out there, the most current that is drawn is around 30-50 amps and that is why we designed the kit with 7 AWG for the 20 foot run. I hope that helps clarify. **Q: Will the alternator charge battery 2 with this while car is running** A: Yes it will. That is precisely one of the features it is designed to do. Thanks **Q: I have a 2020 wrangler with a 240 amp alternator. is this rated to work with my alternator? i will be adding a second battery for low-draw accessories** A: Hello, a 240 amp alternator is definitely a big alternator, however, it is rare that an application would draw more than 40-60 amps at any one time. It is not so much the alternator size that would cause a problem for our isolator it is the draw from the accessories. I would recommend adding up the amperage draw from your accessories when they would all be on and determine the draw, if it is under 140amps then it will work well. If you decide to go ahead and use our Keyline Battery Isolator then you may want to install a large 140 amp fuse or breaker to ensure your alternator won't fry the isolator, but again that would be a rare accessory draw application like an induction cooktop or something similar that would draw over 100amps. Remember that the alternator is only going to push enough amps to power the draw of the accessories and to charge the battery (which also has a low amperage draw). Hope that helps. Thanks for the question. **Q: can this be use to charge a lithium batteries on the second battery?** A: Short answer: it depends. Longer answer: it depends on the Li bank capacity, battery charging specs, alternator specs, resistance of the entire circuit, etc. In my case I replaced 220Ah of flooded lead-acid with 100Ah of LiFePO4 and demand on the alternator actually /decreased/ a bit. If the isolator is already installed you could test it briefly to see what voltage/current from the alternator is like. If you do not already have the isolator a DC-DC sized to your alternator's rating would be a safer bet. ## Frequently Bought Together - Dual Battery Isolator Kit 12V - 140 Amp Voltage Sensitive Relay (VSR) for Dual Battery Setup - Automatic Disconnect Switch for Car, Truck, RV, UTV, ATV, Marine - TKDMR 10pcs 1/0 AWG-3/8 Battery Lugs,Heavy Duty Wire Lugs,Ring Terminals,Battery Cable Ends,0 Guage terminals,Battery Terminal Connectors with 10pcs 3:1 Heat Shrink Tubing - 10pcs 4 Awg - 3/8" (M10) Sanuke Wire Lugs Ring Terminal Connectors Ends, UL Listed Heavy Duty for Battery Cable Lug Wire Electrical Eyelets with 3:1 Dual Wall Adhesive Heat Shrink --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.pt/products/322654187-dual-battery-isolator-12v-automatic-battery-disconnect-switch-12v-140](https://www.desertcart.pt/products/322654187-dual-battery-isolator-12v-automatic-battery-disconnect-switch-12v-140) --- *Product available on Desertcart Portugal* *Store origin: PT* *Last updated: 2026-06-06*