210 Lumens 3W UltraFire WF-502B CREE Q5 5 Mode LED Flashlight with Battery $14.38 + free shipping, Tmart

I disagree with the previous poster. This is a Q5 with included 18650 battery for $15 shipped (albeit probably not protected). I don't see how you can top that.

I disagree with the previous poster. This is a Q5 with included 18650 battery for $15 shipped (albeit probably not protected). I don't see how you can top that.

Maybe you knew this already, but my initial question was: what the heck is a "18650 battery"?

It’s pictured in one of the product photos, and it looks like a AA size battery. But it isn't. If you enlarge that picture it indicates it’s a 2400mah, 3.7 volt cell. This is a specialized battery that you won't find at your local Rite-Aid.

I did some research and it looks like this battery is standard in many compact, high intensity flashlights of this type. You can order it online for as little as $6, excluding shipping.

But get this: it’s a rechargeable battery. According to the package description, this particular flashlight does not come with the required charger, nor does it indicate if the included battery even ships fully charged.

Again, maybe most people already knew that. But for any flashlight amateurs like me who think: "Wow! 210 lumens for 15 bucks, what's not to like?", buy this with the understanding that you're in for another $12 - $20 for a specialized charger. Otherwise you're getting a $15 disposable flashlight that may or may not come with a working battery.