Specifications: Capacity: 4400mAh Chemistry: Li-ion Voltage: 10.8V / 14.4V Cell: 6 / 8 cell Compatible Models: HP 550 SERIES / HP 610 SERIES / HP 615 SERIES HP COMPAQ 6700 SERIES / HP COMPAQ 6720 SERIES HP COMPAQ 6720s SERIES HP COMPAQ 6730 SERIES/ HP COMPAQ 6730s SERIES HP COMPAQ 6735 SERIES / HP COMPAQ 6735s SERIES HP COMPAQ 6820 SERIES / HP COMPAQ 6820s SERIES HP COMPAQ6830 SERIES / HP COMPAQ 6830s SERIES HP 550 Series,HP 550 Compaq 510,Compaq 610,Compaq 615 Compaq 6720s,Compaq 6720s/CT,Compaq 6730s Compaq 6730s/CT,Compaq 6735s,Compaq 6820s Compaq 6830s Please carefully check your battery's Compatible Model & battery picture to ensure compatibility with your Laptop.