CyberPower RB1290X2 Replacement Battery Cartridge, User Replaceable

My CyberPower UPS has two batteries mounted together and separated by a plastic piece. The whole assembly is held together by a kind of sticky mylar piece that is used to pull the batteries out of the cabinet. It makes a "cartridge". I thought that is what I was getting with this product. I thought I would just have to disconnect the battery cartridge and insert the new one.This product just came as two batteries. I had to disassemble the old cartridge and wire in these batteries (using the existing cartridge wire). It not a huge deal but they should not advertise this as a replacement cartridge because it is not.That said, the batteries fit perfectly and work properly. Just be prepared to do a little more work to install them.

My CyberPower LX1500GU seemed to have dead batteries, given the Self Test button in the CyberPower personal edition of the software caused everything to power off! Yet, batteries were listed as fully charged, etc. etc. when it was powered back up.After removing the old batteries, shaking them sounded like a maraca! Yes, I failed to test regularly and these were the original batteries. This time the Self Test button actually worked after replacing. It was also handy that these came charged!The only difficulty was one connector took a while to disconnect. I was worried about ruining the connector. and wire. But connecting the new batteries back up was easy.

I ordered these batteries because my Cyberpower 1500 unit had become totally unreliable and was randomly shutting down my system. To be fair, I'd had it for a while, so I suspected that the batteries needed replacing. The seller shipped them promptly, but actually replacing the battery on the LX1500GU proved extremely difficult -- the terminal wires were so firmly in place that I ended up mangling them in the attempt to remove the old batteries. So now I have a dead UPS unit and new batteries that are useless to me but cannot be returned.

The battery is a direct replacement for the original battery and has been working well and as expected since install over a month ago.

Didn't know I could not return it.