speaking about the "jump boxes" wall mart has a great one for 99.00 it's a 1200amp unit with air compressor (that sucks) and a 400 watt inverter, along with two 12v sockets and a USB socket.
it jumped two of my cars with no battery in the car!

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John HAUL AWAY, OR CRUSHED CARS!!! HELP ME keep the cars out of the crusher! A/C Thread
"as I ride with my a/c on... I have fond memories of sweaty oily saturdays and spewing R12 into the air. THANKS for all you do!

My drivers:
1987 190D 2.5Turbo
1987 190D 2.5Turbo
1987 190D 2.5-5SPEED!!!

1987 300TD
1987 300TD
1994GMC 2500 6.5Turbo truck... I had to put the ladder somewhere!