Watch Battery Changin'

My watch crapped out on me a while ago and I've had this Wenger watch sitting battery-dead for a few years so I thought I'd give it some new life.
I usually take it to a downtown jewelry shop, but that shop is long closed...and, besides, jewelry shops give me the creeps. It also gave me an excuse to buy a cute new tool:
Here's the tool:
It's a case-opener wrench...or watch wrench...or whatever you want to call it. I call it 99 cents + shipping from China. Awesome. And it's surprisingly well made. All those doodads around it are different tips, to fit all your various watch crevasses.
Adjustable.
Here's the back of my watch. Pretty typical, I think, for a water-resistant watch. Lefty loosey.
Unscrew that thing!
Funny, it says "SWISS MADE" on the back of the watch, but the inside says "CHINA." Go figure.
Pop that white plastic case off and there's the battery.
Boom. Working watch.