This is a brand new HP 632421-001 battery. This battery is rated 5200 mAh and will typically last 3 hours on a full charge. The higher the mAh rating, the longer your battery will run before it needs to be recharged again. There are no compatibility issues if your existing battery is rated at 4400 or 4800 mAh.
All our products carry a full 2 Year warranty and every battery is charged and tested before it ships. We provide a 30 day money back guarantee if you are not completely satisfied.