Paul,
I get my fire extingushers at Wal-Mart in the Marine/boater section. They are made by "Kidde" and are aluminum bodied. Rated at 10-B:C (what ever that means?) and can be used on liquid or electrical fires. They are approx. 14" long & 3" in diameter. It weights around 4 lbs. and is my best buddy when I'm driving one of my cars: i.e.
right beside me ready to rock n' roll if needed!
When I was in a local antique car club back in my high school days. One of our members lost a unique (and very expensive) Rolls Royce to a fire.
The guy stated he could have saved the car if he only had had a fire extingusher!
They are the first thing I get for a car when I buy one.
Bob-A