A group 29 from Interstate is pretty much the same thing as a group 31 from someone else.

It's too big for under the front seats.

Under the rear seat for a Carat or GL is iffy dangerous. The seat wasn't made for that. (Weekenders and Westies have different seats). 

Behind the front seats is alright if you make a safe contained for them. If you have just one then you could put it in a battery box behind the driver seat, though you would want to secure it. And insulate the contacts etc.

I've been using that size for a long time now, and it's never been killed by a phone charging all day. Starts without fail. 

> On Feb 17, 2015, at 3:36 PM, Dennis Haynes <d23haynes57@HOTMAIL.COM> wrote:
> 
> I don't see the appeal here. A single group 31 will outperform the pair of these. Of course it depends on where you need to squeeze them is. 
> 
> Dennis
> 
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Neil N
> Sent: Tuesday, February 17, 2015 6:12 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Aux. Battery: Two Group 1 6 Volt "Commercial" Batteries?
> 
> I realize these aren't deep cycle batteries, but at Cold Cranking Amps - 625 Reserve Capacity - 160 Cranking Amps - 750
> 
> http://www.canadiantire.ca/en/pdp/group-1-6-volt-commercial-battery-0100108p.html#.VOPJGChiEy5
> 
> would 2 of these in series power a Truckfridge for 2 hot days?
> (assuming 50% fridge duty cycle)
> 
> Neil.
> 
> --
> Neil n
> 
> Blog: Vanagons, Westfalia, general <http://tubaneil.blogspot.ca>
> 
> 1988 Westy Images <https://picasaweb.google.com/musomuso/New1988Westy>
> 
> 1981 Westfalia "Jaco" Images, technical <http://tubaneil.googlepages.com/>
> 
> Vanagon-Bus VAG Gas Engine Swap Group <http://tinyurl.com/khalbay>