We have diesel so our vehicle battery is in the engine bay, but our Leisure battery is under the nearside front seat, and that is held in place by a 3-4mm thick folded metal plate that is fixed down by a bolt at the top front edge and which pushes down on the extended skirt at the base of the battery to hold it fast.
1988 LHD T25 1.6TD Westfalia Club Joker Hightop syncro
You just need a bracket that will stop battery falling out or shaking loose if your vehicle fell over - thats all they're looking for. Doesn't need to be anything special as long as it does the job.
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