---
product_id: 173975296
title: "MaySpare Dual Battery Isolator Kit 12V 140Amp Voltage Sensitive Relay VSR Double Battery Automatic Charger & Wiring Cable Kit"
brand: "mayspare"
price: "646 Lei"
currency: RON
in_stock: true
url: https://www.desertcart.ro/products/173975296-mayspare-dual-battery-isolator-kit-12v-140amp-voltage-sensitive-relay
store_origin: RO
region: Romania
---

# 140A Capacity 12V Power Complete Kit MaySpare Dual Battery Isolator Kit 12V 140Amp Voltage Sensitive Relay VSR Double Battery Automatic Charger & Wiring Cable Kit

**Brand:** mayspare
**Price:** 646 Lei
**Availability:** ✅ In Stock

## Summary

> 🔧 Power Up Your Adventures with Confidence!

## Quick Answers

- **What is this?** MaySpare Dual Battery Isolator Kit 12V 140Amp Voltage Sensitive Relay VSR Double Battery Automatic Charger & Wiring Cable Kit by mayspare
- **How much does it cost?** 646 Lei with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.ro](https://www.desertcart.ro/products/173975296-mayspare-dual-battery-isolator-kit-12v-140amp-voltage-sensitive-relay)

## Best For

- mayspare enthusiasts

## Why This Product

- Trusted mayspare brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **🌟 Premium Support:** We're here for you—reach out anytime for assistance!
- • **⚡ Smart Voltage Control:** Automatically cuts in at 13.3V and out at 12.8V for optimal performance.
- • **🔋 Dual Power Management:** Effortlessly manage two batteries for uninterrupted power.
- • **🚗 Versatile Compatibility:** Perfect for ATVs, UTVs, boats, RVs, and more!
- • **🔌 All-Inclusive Installation:** Comes with everything you need for a hassle-free setup.

## Overview

The MaySpare Dual Battery Isolator Kit is a robust 12V, 140A solution designed to keep your primary battery charged while allowing accessories to run from a secondary battery. With a smart voltage-sensitive relay that cuts in and out at precise voltages, this kit ensures your vehicle is always ready to go. Ideal for a variety of vehicles, it includes all necessary components for easy installation and is backed by premium customer support.

## Description

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

## Features

- 12V, 140A, 13.3V cut-in voltage, 12.8V cut-out voltage,; Package Include All the Bits and Pieces Needed for a Complete Installation
- Working Voltage: Having Voltage Sensitive Chip,Rely Cuts in at 13.3 Volts and Cuts out at 12.8 Volts to Ensuring Primary Battery is Always Ready for Vehicle to Run.
- Fuction:Like Having Two Separate Power Sources,The Dual Battery Isolator Kit Enables Your Accessories to Run From a Separate Battery While the engine is not running on your vehicle While keeping your Main Battery Charged and Your Vehicle Always Ready to Go and Start When You Want It.
- Compatibility: This battery isolators are small and suitable for almost anywhere, for ATV, UTV, Boats, RV's，marine vehicle, truck, caravan
- Premium service :Provide better service, please contact us if you have any questions!

## Product Details

- **Connector Type:** Screw
- **Contact Material:** Silver
- **Contact Type:** Normally Open
- **Current Rating:** 140 Amps
- **Mounting Type:** Panel Mount, Surface Mount

## Images

![MaySpare Dual Battery Isolator Kit 12V 140Amp Voltage Sensitive Relay VSR Double Battery Automatic Charger & Wiring Cable Kit - Image 1](https://m.media-amazon.com/images/I/71hE4P1kgzL.jpg)

## Questions & Answers

**Q: what type of power runs continuously from the start battery to auxiliary to charge it through the cable???**
A: When the isolator reads the need to charge the second battery it will be charged with the alternator of the vehicle

**Q: Does this item have an internal fuse? Do I only need to fuse my auxiliary battery?**
A: No it does not.  I highly recommend installing a re-settable 150A fuse between your main battery and the isolator.

**Q: are the cables copper clad aluminum or all copper?**
A: Copper

**Q: Can I use this to connect 2 RV batteries in parallel with differet amperage so that the leisure battery only kicks in when the primary battery low?**
A: So they are connected in parallel when charging. The batteries can be of different amperages. However if the non stater battery drops below 12.8 volts it will disconnect from the system so your starter battery does not discharge. Starter and non-starter battery connections are labeled. The yellow wire coming out of the controller can be connected to a switch with the other side connected to ground. If you move the switch so yellow wire goes to ground it will bypass the disconnect and connect both batteries in parallel regardless of the voltage of either battery. Hope this helps.

## Frequently Bought Together

- MaySpare Dual Battery Isolator Kit 12V 140Amp Voltage Sensitive Relay VSR Double Battery Automatic Charger & Wiring Cable Kit
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**Shop now:** [https://www.desertcart.ro/products/173975296-mayspare-dual-battery-isolator-kit-12v-140amp-voltage-sensitive-relay](https://www.desertcart.ro/products/173975296-mayspare-dual-battery-isolator-kit-12v-140amp-voltage-sensitive-relay)

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*Product available on Desertcart Romania*
*Store origin: RO*
*Last updated: 2026-03-16*