Do you have more than 150 amp hour capacity of auxiliary battery? Do you need even MORE power and amperage for your additional accessories or inverters? When our standard 140 amp isolator isn’t enough, you need the Heavy Duty Keyline 300 amp isolator. Key line Chargers has the ONLY 300-amp Dual Battery Isolator on the market! Providing you with everything you need, our 300-amp Dual Battery Isolator kit is the BEST charging solution for heavy duty dual battery systems.
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. The Keyline Chargers Pro HD Dual Battery Isolator is a Voltage Sensitive Relay (VSR) that cuts in at 13.3 volts and cuts out at 12.8 volts to ensure your start battery is always charged.
Unlike other isolators on the market, the Keyline Pro HD Automatic 300 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. This compact battery isolator was built ultra-small to fit almost anywhere! A perfect fit under the hood or anywhere to get close to your batteries.
From package to installation, our Complete Dual Battery Isolator Kit frees you from the worries of having to shop around for every component necessary for a successful install. Kit includes: 1x Smart Battery Isolator w/ mounting screws, 1x 20’ (6 meter) length of 1 AWG red cable, 1x 2’ (61 cm) 1 AWG black ground cable, 2x positive and 1x negative marine battery terminals, 3x 1 AWG copper crimp lugs, 2x red and 1x black heat shrink tubing, 1x insulated ring terminal, and 6x 8” zip ties.
Every Keyline Chargers Professional Grade, Heavy Duty 300 Amp Dual Battery Isolator is backed by an industry leading 3-year warranty. If you are not 100% satisfied with your purchase, simply take advantage of the No Questions Asked, 30-Day Money Back Guarantee!

Dual Battery Isolator Kit Heavy Duty 300 AMP 1000 AMP Peak Voltage Sensitive Relay VSR for 12 Volt Systems - Works with All Battery Types Including Lithium and LiFePO4