Streamlight 22104 SL-B26 USB Rechargeable Lithium Ion Battery 3.7V 2600mAh X Series Dual Fuel Flashlights, 2-Pack

If you have a Streamlight flashlight, these batteries used to be much more expensive. With the price down, I bought two, so with three, I can keep one in use, one as backup, and a third either in reserve or under charge. And speaking of handy, they can be recharged by USB! Being Streamlight factory batteries, there's such a wonderful fit, size, and utility of having these ready. Affordable and able to push the lumens to the limit. One of the better purchases I've made in a while!

So far, so good the batteries last quite some time and make my flashlight super bright on the flipside. They do take quite a long time to charge, but that’s very small sacrifice for the performance of the batteries. I actually have a charger that I put them in I have not tried the plug-in Aspect of these batteries so I can’t comment on that but they charge well. They last quite a while and they put out the juice.

This is my favorite rechargeable Lithium battery to use for my LED flashlight and for use to recharge my cellphone battery.

Works as expected

***WARNING***LARGER DIAMETER THAN CR123A Battery.Will NOT fit SureFire flashlights that take two CR123A batteries, the tube is too small.Use two of the Streamlight SL-B9 rechargeable batteries instead.Good rechargeable battery otherwise, only fits Streamlight flashlights.

Pretty good and still have it after 4 yrs with it.

I originally bought the Streamlight Stinger 2020 which takes two of these SL-B26 batteries. I loved the way they charged and lasted, so I purchased another set of batteries. I have a weird fascination with colloexting various LED Flashlights that typically take the rechargeable18650 size batterie's and after realizing these Streamlight batteries do work in just about all of them, (although they’re 1/8” taller due to their internal charge port), I couldn’t believe how long they lasted. Where a typical 18650 last maybe an hour or so, the SL-B26 has lasted 5+ hours before a noticeable decline. “Few” flashlights won’t allow the cap to screw all the way on due to that 1/8”, but several (90%) will.Only negative is (now) the older charge port needs to update to the USB-C, but not a big deal really, just convenient.I keep the Streamlight on its charger whenever not being used, so it’s not like you have to go through any process. I will say that my chargers stay in garage and in an area where IF a short or something occurred, the house won’t burn down. Only reviewing now as I actually came to buy a couple more sets for RV.

This battery is required for specific power circumstances. It is required in very bright flashlights and laser lights. They take a while to charge so it is best to have a charger that can charge them and also be left on to continuously to charge extra batteries if needed. That way you are not sitting around for 2-3 hours or longer waiting to use the item again because of dead batteries. Just make sure you get the right battery for your application.