[theksmith]

Just wanted to recommend a very small but heavy duty backup jump starter for your vehicle, the JNC300XL:


http://www.amazon.com/Jump-N-Carry-U.../dp/B000XQ9MGE

With it's small size you don't have any reason not to have a backup battery. I carry this until I actually purchase a dual battery controller and second battery.

This is the smallest one I know of that still has the power to turn over a decent size engine. it has 900 peak amps and beefy cables and clamps. I was weary of something this small, but I have personally disconnected my main battery and started my 4.7HO V8 with this little thing. Now I have not tested it in 0* weather, and I don't expect it to work on a large diesel, but for what it is, it's impressive.

Those other little small brick shaped jump starters that you put in your cigarette lighter to crank your car might work for some really tiny car engines, but your going to need something at least this big for most jeep/truck engines. You'll notice most products in that category (like the Porta-Jump) get horrible reviews.