This is a brand new Compaq Presario C300 battery. This C300 Presario battery contains the very best Li-ion cells on the market from Samsung. An important specification to look for with rechargeable batteries is the mAh (mili amp hour) rating or Whr (Watt Hour). This battery is rated at 5200 mAh or 58 Whr. This is the highest rating available for a 6 cell battery pack. 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 or a lower Whr.

We are a US-based business with knowledgeable support staff to assist you before and after the sale. Yes, we have a phone number and real people answer your call! Free technical support is available if you need additional help in diagnosing power problems with your battery, ac power adapter or battery meter software.

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. We are so confident in the quality of our batteries, we will pay for any and all shipping expenses if our product fails to perform in the first 30 days you have our battery.

You can expect about 2 - 3 hours of run time with this computer battery when new, depending on your energy use. If you are looking for even longer battery run times, check out our HP-A73XT.