HWG M17x R4 Battery (9-Cell) Compatible M17x, M17x R3, M17x R4 Series, Fits P/N BTYVOY1 C0C5M 318-0397 5WP5W 7XC9N 05WP5W 07XC9N (11.1V 90Wh)

This is a somewhat mixed review, so I suggest you read it. The battery initially worked fine, but after 8 mo. it stopped taking a charge. Battery meter would indicate 92%, then a few weeks later, 72%. This reading was apparently incorrect though because if I disconneted power, the laptop would turn off.I contacted the seller through Amazon and they were flawless. There response was very fast, and they asked for a description of the problem. They then asked to confirm my address, and I had a new battery the next day.Now, I can of course say that I was disappointed that the battery failed, but I cannot fault the seller. Dealing with them was straight forward and I was delighted at ease of dealing with the problem.What is important to me with this kind of purchase is that if something does go wrong, I don't find myself dealing with some fly by night company that shows up on Amazon one day and is gone the next. HWG was there when I needed them to be, and they absolutely stood behind their product.

didn’t work

Holds power as well as the last one. I have only had it a month so I don't know about the longevity of it.

Dead on arrival. Junk.

Perfect