Lithium Battery Charger Flashing Red And Green

This is a very nice headlamp, without two levels of white light, a red light and a flashing red light.  Having the battery pack on the back makes it much easier to balance and the straps are adjustable over a wide range.

My APC UPS sounded off every few hours with beeps and a flashing red light to let me know it was time to replace the battery. I ordered online and the battery arrived sooner than expected. I installed it and it's been working fine since. The part I especially like, I didn't have to shut everything off to install.

As many others mentioned in the reviews, these batteries are now new old stock, as the newest ones were made in 2022 and will arrive completely discharged. DO NOT give up on them - the charger will initially show an error (chamber and calibration light flashing) - keep taking the battery off and putting it back on, and eventually it will start to charge. The key is to not leave it in the charger if the charger is showing the error code, you have to remove and replace the battery until the charger shows that it is charging (chamber light and 50% light flashing). After a few hours the 50% light should glow solid and 80% should start flashing, and eventually it will charge fully

Bright white light is very bright. Red/red-flashing light is cool -- not sure if I'll ever use it. Good fit and balance (with batteries in back). Lightweight and comfortable. Looks suitably geeky. Very happy with my purchase.

I love the Watson charger. It's fairly fast and I love the fact that it changes from a red light when charging to a green light when fully charged. I also like the fact that it doesn't require a cord to plug it in. You just pop out the prongs and plug them into the wall outlet. Sweet!

I've only charged my batteries once, but the charger worked just fine. I like the red/green light indicator for charging status. I never would have found the charger I needed without the help from the Live Chat pro. Thank you!

Excellent quality charger and batteries. The charger at bright status LEDs, red with charging and green when fully charged. Very compact. Comes with the USB cable only. You can use a wall charger of your cellphone so there is no need to purchase one.

This lithium battery is very reliable.

The Watson NP-BX1 Lithium-Ion Battery Pack and Charger Kit is perfect as a second backup battery. The charger has an easy to see charge indicator light !

When the battery is full charged, the LED color changes to green from red. LED was also green when the battery was uncharged. I charged the uncharged battery for several hours so the LED turned red from green, then it turned green again when its full charged.