RE: Connectors for Battery
You are looking for these:
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http://www.powerwerx.com/anderson-powerpoles/powerpole-sets/sb175-sb-series-175-amp.html
>
The large Anderson Power Poles.  That is probably what you saw, sold by
someone that sells Vanagon stuff online.  One warning.  To attach to the
wires (big) that you run to the battery or to attach to your jumper cables
you will need a very beefy crimper made for just that or you will need to
solder the connections, you will need a small torch for that.