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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60W Type-C To USB C To Micro To Lighting Fast Charging Cable Adapter Kit for IPhone 14 15 13 Pro OTG Converter Multi Storage Box
Aliexpress UK
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
Portable Solar Panel USB 12V Charger Mobile Phone Folding Kit Foldable Outdoor Camping Power Bank For iPhone Charging Battery
Aliexpress UK
Suitable for most 12V charging systems- Surge protection. Dual Battery Isolators also feature surge protection and a L.E.D indicator designed to alert the user when the unit is engaged. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery.
eBay
DIY 18650 Battery Storage Box Mecha style 8 Cells 18650 Battery Power Bank Case Fast Charging Mobile Power Kits No Soldering
Aliexpress UK
Suitable for most 12V charging systems- Surge protection. Dual Battery Isolators also feature surge protection and a L.E.D indicator designed to alert the user when the unit is engaged. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery.
eBay
High-Efficiency 500W-2000W Solar Panel Kit – Power Your RV Boat Car and Home with 18V/36V Charging
Aliexpress UK
Heavy duty 200 Amp 12 volt relay Ideal for split charging systems or heavy load switching. The kit has everything that you need to install a split charging system in your vehicle including a relay that prevents your main battery from draining while the engine is stopped.
eBay
1 Section 218650/1700 Fast Charging 5V2A Cylindrical Aluminum Alloy Mobile Power Bank Kit with Type C Interface
Aliexpress UK
All the leads are supplied ready made up for you to a very high standard. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery. So you will always be able to start your vehicle when you need to.
eBay
DIY Free Welding 1X 18650/21700 Battery Aluminum Power Bank Kit 5V 2A Type C Fast Charging Battery Storage Case Box
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. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery.
eBay
60W Multi Type-C To USB C To Micro USB To Lighting Fast Charging Phone Cable Kit for IPhone 16 15 14 Pro Data Cable Storage Box
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. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery.
eBay
5V 5.5V 160mA 200mA 500mA 1W 2.5W Solar Panel With 5V 1A Solar Lithium Battery Charging Controllers Display Diy Kit
Aliexpress UK