True® Medium Dual Battery Kit ( DBK12MED )
$60.00
Item number: DBK12MED
Suggested retail price $149.00
The True® Medium Dual Battery Kit (DBK12MED) is a smart, under‑the‑hood solution designed to safely connect and manage a second battery in trucks, Jeeps, RVs, boats, and 4WD vehicles. It includes the TRUE Smart Battery Isolator, which automatically charges the auxiliary battery while protecting the primary battery for reliable starts and essential vehicle operations.
Inclusions:
- 10 ft Red #6 cable with attached lug ends to fit the TRUE Isolator.
- 2 ft Black #6 cable with attached end lugs for 2nd battery ground
- 2 – 5/16” crimp on end lugs
- 2 – 3/8” crimp on end lugs
- 2 – sections True Special Adhesive shrink tube
- 5 – zip ties
Description
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This is the perfect kit to not only connect that second battery under the hood of your Truck or Jeep but it also includes the TRUE Smart Battery Isolator to automatically control the charging of the second battery while providing voltage triggered isolation of the primary battery to reserve its charge for vehicle starting and primary operations. The unit will work to connect different types of batteries and keep them separated when there is no charging voltage available so that they do not “balance” and reduce each other's efficiency like if they are paralleled without smart management.
Got a winch or plow you want to be serious about using but don’t want to worry about overworking your alternator or discharging your primary battery? Then the TRUE Medium Dual Battery Kit is exactly what you need.
Want to run those off-road lights and high amp stereo without worrying about getting stranded? Then the TRUE Medium Dual Battery Kit will handle the batteries for you!
As with all the TRUE products, it features easy installation requiring no connection to the alternator or ignition.
All the TRUE kits include proprietary built cables that use special adhesive-lined shrink tube to provide a fully waterproof, corrosion-proof connection between cable and lug. The adhesive also provides the connection extra strength, eliminating the possibility of the lug pulling off even in high stress and/or vibration applications. A TRUE exclusive!
Trucks & 4WDs
Powers winches, lighting, fridges, and inverters from an auxiliary battery while protecting the starter battery from drain—ideal for off-road, worksite, and overland setups.
Cars & SUVs
Supports aftermarket accessories like sound systems, dash cams, and emergency lighting without compromising engine start reliability.
Boats & Marine Vessels
Separates house and engine batteries, ensuring navigation, bilge pumps, and onboard electronics run independently and safely.
RVs & Campers
Keeps living space powered with solar, lighting, and appliances while maintaining a charged starter battery for travel.
Commercial Fleets
Enables reliable accessory use (e.g., GPS, radios, refrigeration) in delivery vans and service vehicles without risking downtime.
Emergency and Service Vehicles
Essential for maintaining the charge of batteries dedicated to life-saving or essential service equipment, ensuring reliability when the vehicle is stationary or idling.
“The True® Lithium Kit was a game-changer for my 4WD setup. Easy to install and rock-solid performance on long trips.”
— Mark T., Minnesota
“Installed it in my boat—no voltage drop, no drama. The waterproof cabling and smart relay are top-notch.”
— William L., Utah
“Perfect for my caravan. The automatic battery management saves me time and worry—highly recommended.”
— Dave R., Colorado
Amazon Rating
-Automatically charges the auxiliary battery while protecting the primary battery.
-Voltage-triggered isolation ensures the starter battery always retains enough power for ignition.
-Compact medium kit tailored for trucks, Jeeps, and similar vehicles.
-Simplifies installation with pre-terminated cables and hardware included.
-Prevents dead batteries by reserving charge for starting and critical vehicle systems.
-Provides consistent power for accessories such as winches, lights, inverters, or audio systems.
-Ensures both batteries are charged efficiently without manual intervention
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Our perks
1-year all-inclusive warranty
We’ll replace it with a new one
Free shipping on returns
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Free, contactless delivery
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