Imren 9V Rechargeable Lithium Batteires, 3600mWh USB 9 Volt Li-ion Rechargeable Battey Long-Lasting，with 4-in-1 USB-C Charging Cable, 1.5 Hrs Fast Charging for Smoke Detector/Alarms,4 Pack

AWESOME PRODUCT !! Didn’t even know they made something like this !! We were going through 9v batteries like crazy in our ceiling fan/light remote !!! This is great !!

I purchased an earlier version/brand. These are upgraded bottom glows red on charge and goes green when complete + Also the four usb 2 type is better. Power seems good but too soon to tell. Im using them for smoke alarms

These rechargeable batteries do not hold a charge. I bought them because I have a built in tuner in my guitar that I forget to turn off, so I'm wasting a lot of money on batteries. I charged all 4 batteries and put one in my guitar, and it worked fine. I put the others back into the original packaging for storage and put them in my gig bag. Got to a gig and the battery in the guitar was dead. Tried to replace it with one of the others, and that was dead too. Totally worthless to me.

Buen producto

Your experience may differ, but the batteries I received did not hold a charge very long. If you use these batteries, plan on charging and then directly installing. They do work, and will save money and the environment from the waste.

I had a few of these fully charged and they self-discharge simply sitting. I was also using several of them them for multimeters which also self-discharged and the multimeter didn't work when I needed it. Also using for fire alarms but nope these are more of a nuisance and certainly aren't worth the money.

I can use these in my appliances even when plugged in and charging. Not if they are supposed to be, but when I need to use my kitchen scale for long periods of time, it is awesome knowing it isn’t going to die in the middle of a project!

These batteries are great! They are easy and fast to charge and they hold a charge for a good amount of time. I'm very happy with this purchase.