When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery. So it does not drain your main starter battery and you will always be able to start your vehicle.
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30W Solar Charger System IP65 Car Battery Solar Panel Charging Kit 18V Solar Battery Charger Board For Car RV Boat Motorcycle
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Dual Battery Isolators also feature surge protection and a L.E.D indicator designed to alert the user when the unit is engaged. - Suitable for most 12V charging systems- Surge protection. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery.
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30W 4-in-1 Magnetic Wireless Charger for iPhone 14-16 Pro Galaxy S22-S24, Fast Dual Charging Station for Phone/Watch/Headset
Aliexpress UK
5m full kit(VSR without LED). VSR Features. Easy to install VSR Specification. 1x VSR(with/without LED) with fitting hardwares. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery.
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DIY 21700 Battery Power Bank Kit 30000mAh Camping LED Light, PD/QC 22.5W Fast Charging USB-C/Micro Input Aluminum Case
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7m kit The kit includes everything you need for setup dual battery charging system When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery. So it does not drain your main starter battery and you will always be able to start your vehicle.
eBay
4000W Solar Panel Kit 12V To 110V/220V – 6000W Inverter 12V Battery Charging for House RV Camping & Emergency Power
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Models are available up to 400W and unlimited multiple units can be connected in parallel to increase output power. Heat Shrink. An unlimited number of units can be connected in parallel. Input fuse (not replaceable).
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UGREEN USB C Link Cable for Quest 2 Headset VR USB3.2 Gen1 High Speed 5Gbps 5m Charging Cable 60W USB C to Type C Link Cable
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Simply connect the relay between your starter battery and leisure battery and the relay takes care of everything, making sure your starter battery is not drained for when you need to get going again.
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Portable Power Bank Kit DIY 2x18650 DIY Fast Charging- Power Bank Shell Case Box 10x4x2cm/4x1.6x1-inch 2.1A5V Compact-
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Dual Battery Isolators also feature surge protection and a L.E.D indicator designed to alert the user when the unit is engaged. - Suitable for most 12V charging systems- Surge protection. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery.
eBay
Universal Mobile Phone Charging Port Dust Cleaner Kit Anti-lost Dustplug Cleaning Brush For iPhone Xiaomi Samsung Cleaner
Aliexpress UK
Dual Battery Isolators also feature surge protection and a L.E.D indicator designed to alert the user when the unit is engaged. - Suitable for most 12V charging systems- Surge protection. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery.
eBay
1000W 12V Solar Battery Charger & Maintainer Portable 12 Volt Solar Panel Charging Kit for Car Automotive Boat RV Marine
Aliexpress UK