I only put the auxiliary battery and compressor with its air tank in when I need them. The battery is in a battery box and has the Ctek D250S Dual bolted on top so I can charge it from the main battery of solar panels. It sits behind the rear seat in front of the fridge when I take it.
The compressor and air tank are in a ply box which goes either in the boot or behind a front seat in the foot well.
It saves me carting 50 or more kilos around when I don't need to.
Cheers
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