Feature: 1. VOLTAGE SENSITIVE RELAY: Automatic manual 140Amp double battery isolator is all you need to charging two battery systems. Voltage Sensitive Relay (VSR) cuts in at 13.3V and cuts out at 12.8V to ensure your primary battery is always charged and ready to start your vehicle. Which is like having two separate power sources for each battery while only having one alternator 2. UNIVERSAL COMPATIBILITY: Like having two separate power sources, the double 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, power for any ground or marine vehicle including ATVs, boats, cars, trucks, RVs, and yachts; Nice versatile solution for all automotive power needs 3. EASY TO INSTALL: The VSR split charging relay kit comes with full installation accessories and cables(battery cables, battery terminals, copper lugs, heat shrinks, cable ties) that make it easy for users to install independently to vehicles, boats, recreational vehicles, and other equipment 4. SAFE AND EFFICIENT: The double battery isolator efficiently manages and protects power, preventing over discharge of the main battery and ensuring full charging of the second battery. With quality materials and an IP68 water proof, dusts proof, and vibration proof construction, battery isolator delivers high performance even in harsh environments 5. WIDELY USED: Double battery isolator kit can be widely used in camping vehicles, recreational vehicles, caravans, etc., very practical. Meet your off road needs even in dusty, wet and unexpected extreme weather conditions Specification: Item Type: Double Battery Isolator Kit Rated Voltage: DC12V Rated Current: 140AMP Water Proof Grade: IP68 . Package List: 1 x Battery Isolator 1 x 7AWG Red Cable 7.0m 1 x 7AWG Red Cable 0.5m 2 x 7AWG Red Cable 0.25m 1 x 7AWG Black Cable 1.0m 2 x Fuze Holder 4 x 60A Fuzes 6 x Crimp Connectors 10 x Adhesive Cable Tie Mounts 19 x Mounting Screws 10 x Cable Ties 2 x M8 Battery Terminals 6 x Red Heat Shrink Tubes 1 x Black Heat Shrink Tube 2 x User Manuals