3.7V 700mAh 702540 Lipo Battery Rechargeable Lithium Polymer ion Battery Pack with PH2.0mm JST Connector

Very happy with this product, exceeded my expectations

There’s not much to say about these. It’s a relatively small battery and charged/discharged fine. I can’t say how accurate the capacity rating is but it worked great for my use.

Got this to replace the battery in cheap Chinese Electronic Stethoscope/Pulse-Ox/EKG combo after the battery would hold a charge. The replacement battery pack works fine with and it fits in the battery slot. The only modification I had to do was I had to pull out the lock-rack on the stethoscope, because the connector on the battery back was too big. I also had to shave off the guide-rail on the connector to get it to fit with the correct polarity since the rail was pointing outward and was hitting the edge of the power slot.Other than that, he powers on, charges, and so far seems to work well. If you're gonna do this, make sure you have the polarity correct, otherwise you might end up with the 'magic smoke' and destroy your electronic....or battery.

I'm reluctant to give a review too early on batteries. However this battery was exactly what was advertised and easy to install. It did as well work immediately upon install.

Seems like a good product and definitely a good price. It arrived quickly.I blew out the charging circuit on an Adafruit Feather board because I stupidly assumed polarity on all battery connectors would be the same. Turns out this one was reversed. Lesson learned.

This will ruin an Adafruit Feather as the +/- is wired in reverse. Other than that it works fine and you can always switch the pins.