There are many brands and models of this kind of product but I like
these best and have installed them in several vans.

SurePower 1314A and 1315A

This place is offering them for $55 and free shipping if you use a
discount code when you order.

http://www.ase-supply.com/Sure_Power_Battery_Separator_s/154.htm

Free Shipping on any Sure Power products in stock
(while supplies last)
Use code: SUPW

Mark

Richard A Jones wrote:
>> Let's not confuse isolators (diode devices) with relays or contactors.
>
> Or combiners!  I like:
> http://yandina.com/c100InfoR3.htm
> It would certainly fit where the WEsty battery relay lives, but is
> better mounted where you can see the LEDs--like behind the driver seat.
>
> Richard
>