9V Rechargeable Batteries, USB C 9 Volt Battery with Type C Fast Charing Cable for Smoke Detectors,Medical Devices,Clocks (2pcs)

Works really well in a tens unit I have. A charge lasts days vs hours using ni-cads. Rapid charging but not necessary. This purchase was for two units plus a dual USB charger cable. Very satisfied.

What a brave new works we are living in! Just plug right into the battery and charge! So awesome. They seem to die a little faster than traditional ones but that’s fine. Been using for over six months and they still work. Excellent value of course. They charge quickly.

The batteries charge fast and work great!

First impression, these batteries are super light as they are actually 3.7v 1000 mAh which converts to a 9v around 400 mAh approx. These batteries will drain on their own faster than alkaline so advertising them for low draw devices is kind of misleading. I'm using this in a meter that measures square footage of buildings and area. This battery is perfect if you are constantly using your tool and need to recharge it, this will save you a ton.I don't recommend using it in long time rarely used temperature measuring tools or smoke detectors as you'll find yourself charging these all the time. In comparison alkaline 9v batteries are anywhere from 450-600 mAh.A word of warning because this is converting the voltage from 3.7 to 9v when it's ready to die, it'll just suddenly die. This is a normal behavior and not a defective battery.Overall I highly recommend these 9v batteries for high usage tools, and not for backup batteries for keeping clocks during power outages or backups for smoke detectors. I mean you can use it for smoke detectors just don't be surprise if they don't last nearly as long as your alkaline batteries you are replacing.

Good quality product

I am using these in meters and other low draw devices. So far they are working great. Unfortunately the 1000mAh rating is misleading. That rating is at 3.7 volts. This means the battery shod deliver around 400mAh at 9 volts. For my uses this is not an issue but I find the advertising of 1000mAh inappropriate.One star deducted for misleading advertising.

These Sashine 9V rechargeable batteries are like tiny superheroes for your gadgets. Equipped with a USB C fast charging cable, they swoop in to save the day just when your smoke detector decides it’s time for an impromptu midnight rave.Charging these bad boys is quicker than a coffee run, and they hold their charge longer than a toddler’s fascination with cardboard boxes. They snugly fit into all my devices, from smoke detectors to clocks, and even the occasional medical gadget that seems to consume power faster than a teenager with WiFi.Say goodbye to the endless cycle of buying new batteries and hello to the eco-friendly, wallet-friendly revolution. These batteries are reliable, easy to charge, and bring a touch of convenience to everyday life. They’re a small investment for a big boost in peace of mind—and your gadgets will thank you!

Interesting rechargeable battery. I'm seeing 8.8v and 9.1v on the two batteries upon arrival. Recharges via USB.I'm not about to try and take the battery apart, but I think internally it's a lithium battery with a little boost converter and recharge circuit. If so, this boost is probably going to cause an unstable voltage, so I would not recommend using this for anything that needs some stability in the battery voltage (eg multimeters). For other items not sensitive to voltage input fluctuations like smoke detectors or camping lights, this probably works great.It saves from having to buy new batteries. At the rate I go through my 9V batteries (only 4/year) and assuming 1000 cycles, these batteries will last me decades!