Automatically combines two batteries when charging and isolates the two batteries when not charging,which can widely used in 12v camper van trucks, caravans, and camping applications. When your engine is switched off, the relay will isolate your leisure battery(s) from your main starter battery.
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FOXSUR 20A/10A Car Motorcycle Battery Charger 12V/24V Smart Charger Lithium AGM GEL Lead-Acid LiFePO4 Battery Chargers1 Set
Aliexpress UK
(1 BB1230 Charging Unit. All of the benefits of advanced charging without any of the drawbacks. 4) Current is NOT taken from the input battery and given to the output battery. Manual mode and regenerative braking mode allows you to override this.
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3.7v Charger for Wltoys V911 H36 E010 F929 Charger Battery conversion Cables Set for Syma X5C Syma X5SW Drone RC Quadrocopter
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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
New DIY High Quality Hello Kitty Charger Data Cable Case Protector and Winding Kit for Apple 18W 20W Charger Adapter
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
30W Solar Trickle Charger IP65 Car Battery Solar Panel Charging Kit 12-24V Solar Battery Charger For Car RV Boat Motorcycle
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
1-5 PCS Monocrystalline Solar Panel 10W Solar Battery Trickle Charger 12Volt Power Solar Panels Battery Charger Car Van Boat Kit
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
4Pcs/set Marvel Charger Smart Cover Cute Cartoon Charger Protection for Samsung 25W Data Cable Charging Decoration Accessories
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
4Pcs/set Cable Protector For UK Plug 20W USB Fast Charger Case For iPhone Charger Protection Spring Cable Winder Accessories
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
FOXSUR 20A/10A Car Motorcycle Battery Charger 12V/24V Smart Charger Lithium AGM GEL Lead-Acid LiFePO4 Battery Chargers1 Set
Aliexpress UK