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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8 Slots 21700 Battery Case DIY Kit Mecha Transparent Quick Charge Flash Charger Battery Case Kit Power Bank Box Type C
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
500W12V Photovoltaic Solar Panel, 1000W Power Bank Kit 100AController Solar Plate For Home/Camping/RV/Car Fast Battery Charger
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
Solar Panel 150W ETFE Flexible Solar for Family Camping PV Single Crystal Panel Portable Power System Charger Set
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
1500W Solar Power System 220V/1500W Inverter Kit 600W Solar Panel Battery Charger Complete Controller Home Grid Camp Phone
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
320w 160w 300w lightweight solar panel aluminum frame 12v battery camper charger kit photovoltaic panel system for home balcony
Aliexpress UK
Brought never got round to fitting, now no longer needed.
eBay
240w 120w 200w 100w flexible solar panel 12v battery charger kit upgrade photovoltaic panel for home camper car boat balcony RV
Aliexpress UK
【Fit All types of Battery】 -- Fit for Lithium Battery, Lead-acid Battery, AGM Battery etc. 【Delay Setting Function】 —— The new delay function avoids frequent switching on and off of the isolator due to unstable current, which prolongs the isolator and battery life.
eBay
12v flexible solar panel kit 100w 200w 300w solar panels with solar controller for boat car RV and battery charger
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
YSIDO 533 200mm 5inch Carbon Fiber Frame Racing Drone Frame Carbon Fiber X-type Split Kit for Five33 FPV RC Quadcopter Drone
Aliexpress UK