Not the cheapest but these seem to be gaining popularity with car owners. Small, no maintenance, non toxic, low mess when used.
80% smaller & has 5x the discharge time of a traditional fire extinguisher. Makes no mess, requires no service and will not cause additional damage to any of your possessions.
elementfire.com
The Element carries no rating, and puts you dangerously close to the fire. There's no way I'd touch them.
I use Amerex Halotron extinguishers in my vehicles, mainly because I don't want the corrosive mess of a dry powder discharge on electronics.
@Jlarson is right in going as big as possible. My 2.5-lb extinguishers are probably in the barely-or-not-quite-adequate category, but they're what I have.
Zoro has the best prices I've found. Although the last one I got a few months ago was a LOT more expensive -- like twice -- the ones from a few years ago. I still couldn't find a better price, and with the right coupon it can help.
Order Amerex Fire Extinguisher, 2B:C, Halotron, 2.5 lb, B385TS at Zoro.com. Great prices & free shipping on orders over $50 when you sign in or sign up for an account.
www.zoro.com
Again, not the best idea.
That 2.5LB Halotron has a 0A and 2B rating. 2.5LBS of ABC dry powder has a 1A and 10B rating. So, you'd need 5 of those Halotron units to match the ability of one home kitchen disposable can on a liquid fire, and the Halotron will do NOTHING if your upholstery caught.
As for the mess, any electronics under the hood should be weather sealed, and the ash from burning plastics is FAR more corrosive than ANYTHING from an ABC drychem. Plus if you're THAT worried about it, get a Purple K drychem and simply hose off what it leaves behind.
I keep a 1A:10B:C 2.5LB drychem extinguisher in my Jeep. Yes, they're still limited in what they can do, and without a hose you need to pay attention to keep them upright to feed the siphon, but they're still several times better than anything else the same package.
In my shop (and house), I have several 3A:40B:C 5lb drychem extinguishers. A few years back, I used one to put out a fire on a neighbor's deck. It had consumed a potted plant on his deck and at least a square yard of astroturf was a burning "tar" puddle as the flames climbed his siding. 5lbs of drychem MOSTLY put it all out, but I ran home and got a second one because there was enough heat left that a vinyl gutter with some dry brush in it re-ignited. I can assure you that standing there with too little of an extinguisher is not a good feeling.
