Go to Amazon Sites : br br Amsahr Replacement Battery for HP (4210S) br br 18 Months Manufacturer Warranty 100 Satisfaction Guaranteed br 100 Compatible Non-OEM Lithium Ion Li- ion Long Life Battery Rechargeable with No Memory Effect and Power Surge Protection br 4400 mAh 144 Volts 8 Cell br Protective Retail Packaging Each Product is Sealed with Anti-Static Shield Sleeve