Passenger Swivel Plate Options.

Hi humans,

Is there a preferred swivel plate for a single captains chair? I want to do my passenger seat.
There is some very cheap ones on eBay around $250, or the JustCampers option at $495 which are all out of stock. Or the KombiLife one at $575.

I want to put a battery under that seat so I want to get the right one.

Make sure its a sealed battery then

Are the eBay ones ADR compliant?
I have one from transport seating which is quite heavy and well constructed.

I am interested in responses to this question too.

I am considering a lithium battery - the largest that fits under the passenger seat - and I need to know the dimension available with the various swivel mechanisms.

Thanks.