This is what I have:
.
It's a Kidde Auto Extinguisher. Rated B-C (flammable liquids and electrical fires). It's not top-of-the-line (e.g. not high-capacity, not rechargeable, and not A-rated for cloth/paper), but it's inexpensive, small, and provides some coverage against more-common auto-related situations.
Has a pressure-test button that I check periodically, per instructions. As far as its useful life, the maintenance instruction label says, "This product must be removed from service 12 years after date of manufacture." Date-of-manufacture is included on the label. Arbitrarily, I'll no doubt replace them before 12 years. That seems like a long time to me.
Beyond that, I'll yield to our firefighting – and related – professionals on the forum.