9V Rechargeable Battery Pack,2-Pack 1000mAh Li-ion USB Battery with Micro USB Port for Alarms Fire, Multimeters,Wireless Microphones,Smoke Detecto...

This product works better than the other rechargeable 9v batteries I've used before. I like how fast it charges - it only takes a couple of hours. The batteries have been in my smoke detectors and they're working great so far. This battery is a much better value than buying disposable batteries. I'm very happy I'll never have to buy 9V batteries again thanks to these rechargeables.

The battery makes this humming high tone noise . I bought it for my guitar and it is not usable

This battery will save a lot of money to me, I have to purchase almos all the months batteries for my multimeters, now are a past issue.... Fast time to recharge and a good duration.

I cannot lie. I hate 9V batteries. They are expensive. They have a low mAh relative to their size. They always turn up dead at just the wrong time. And while I always have plenty of spare AA, AAA, CR2032, and other batteries lying around, 9V batteries are perpetually out of stock in my battery drawer. What I wouldn't give to have a collection of Eneloop rechargeable 9V batteries! Regrettably, Eneloop doesn't make a 9V rechargeable. The good news is that someone else doesspecifically, some rando Chinese company with a name that seems to have been created when someone's cat walked across a keyboard. Nevertheless, it's a rechargeable 9V. Rejoice! Wait. What? It uses Micro USB and not USB-C? Now *that* is annoyingand also pretty inexcusable for a new 2023 product. Micro USB ports are almost as annoying as 9V batteries. Nevertheless, it is a rechargeable 9V. Rejoice! This battery is, aside from the terminals, all plastic. It features a generic green cover that is cleverly labeled "9V Size USB Battery". It is surprisingly light. A 9V Duracell Alkaline battery I happen to have sitting around weighs 44g. This LiPo [lithium-ion polymer] rechargeable weighs only 20g. Despite its light weight, its 1000 mAh rating is very good for a 9V battery. There seems to be a trend emerging with rechargeable batteries that eliminates the battery charger entirely in favor of an integrated USB charging port on the battery itself. I recently purchased a pair of NP-F70 batteries that take this approach. It works very well. These 9V take the same approach (albeit with an outdated Micro USB port), a welcome decision that really streamlines the process of charging them. Charging these batteries is simply a matter of plugging in a Micro USB cable. A small red LED next to the charging port illuminates while the battery is being charged. Once fully charged, the LED turns blue. These 9V rechargeables work fine in both my multimeter and my sound meter. I don't have a use case that would quickly deplete a 9V battery so I'm not in a position to test this aspect of their performance. If the manufacturer's specs are correctnot something one can necessarily assume to be the casethen they should outperform standard 9V batteries. The bottom line? Despite the Micro USB port for charging, I am delighted to own 9V rechargeable batteries and I am delighted to be able to charge them without the use of a separate charger. These batteries eliminate a pain point for me. I absolutely recommend them.

El producto cumplio todas mis expectativas.