2PCS 3.7V Lipo Battery 3700mAh 103395 Lithium Polymer ion Battery Rechargeable Lithium ion Polymer Battery with JST Connector

Mounted them in series to replace the wasted ones on a Zenith portable DVD player, worked like a sharm, lasting longer than the original due to its higher capacity and fitted perfectly inside the battery module.

I purchased these 3.7V LiPo batteries for a project, and overall, they work great and deliver reliable performance. The capacity is as advertised, and the batteries hold their charge well during use.The only downside I encountered was that the JST leads were reversed compared to my setup. While this could be an issue for some users, the good news is that the leads can be de-soldered from the pads and replaced or swapped with the correct leads. It’s a bit of extra work, but if you’re comfortable with basic soldering, it’s a manageable fix.If you don’t mind making this small adjustment, these batteries are a solid choice. I would have given them five stars if the leads were properly configured out of the box. Overall, they’re great value for the price!

Product advertises a JST 1.25mm connector on the battery, but this battery has a JST 2mm.

I had a Trak-4 GPS tracker that never worked right - battery problems from day 1 and Trak-4's customer service was chronically useless. This is longer than the original battery (a 103379), but it fits in it fine (the older 12V Trak-4; there's apparently now a newer model that is smaller). The polarity on the jack had to be switched, but that's fairly easy to do with a tiny flat blade screwdriver. The first charge didn't seem to work (the Trak-4 died in just 3 days when it should have lasted a few months), but the second charge took and now it's working better than it ever did before.

Batteries work as expected. Saw a consistent 2.6 Ah capacity after 10 cycles instead of the advertised 3.7 Ah. The PCM cuts off at 2.8 V on the model that I received.