Here's a super-sized power bank, able to keep all your gadgets charged many times over. It offers both USB charging and a 12V accessory socket - with a suitable inverter you can even power small mains devices. It also features a digital voltmeter, to allow the state of charge to be judged.The design here includes a rugged, waterproof case, with a storage compartment for leads and accessories. It's ideal for a camping trip, particularly when paired with a solar panel for recharging.
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