Let me start by saying these Tokeyla 18650 batteries with the included charger have been a rollercoaster of experiences for me. The convenience of having both batteries and charger in one package is great, especially when you're in a pinch and can't find these locally.

The charger itself is pretty decent - I love that it's USB powered (no hunting for AC adapters!) and can handle multiple battery types. The red/green LED indicators are clear, though I did notice sometimes it's finicky getting the batteries positioned just right to make contact. One major plus: the safety features give me peace of mind when leaving batteries charging overnight.

Now about those batteries... Here's where things get interesting. In my UV flashlight, they perform like champs - brighter output than my old batteries. But like another reviewer mentioned, they do seem to drain faster than expected and can get warm with extended use. I've been charging them every couple days with moderate use.

The biggest letdown? That advertised 5000mAh capacity seems... optimistic at best. In my testing (using a constant current load), I'm seeing about 1200-1300mAh - roughly 25% of what's promised. That button top design also caused compatibility issues with some of my devices that expect flat-top cells.

For casual use in flashlights or low-drain devices, they're serviceable, especially considering the price point. But if you need serious power or accurate capacity ratings for critical applications, you might want to look elsewhere or temper your expectations.

Final verdict? They're okay for the price as backup power sources, but don't believe the hype about that 5000mAh rating. The included charger is actually the star of this package in my opinion!