CWK&reg; New Replacement Laptop Notebook Battery for HP Compaq 550 Series Compaq 510 511 610 6720s 6730 6735s 6820s Compaq 610 615 HSTNN-LB51 451086-421 HSTNN-IB51 451086-142 Compaq 510 511 610 615 HSTNN-LB51 451086-421 HSTNN-IB51 451086-142 HP Compaq 511 610 615 491278-001 HSTNN-LB51 451568-001 451545-361 HP 550 Compaq 610 510 511 HSTNN-IB62 451085-141 451086-121 HP Compaq 610 615 550 HSTNN-FB52 NBP6A96 451086-362 HSTNN-IB51 -IB52 491278-001 500765-001 500764-001 GJ655AA#ABH Condition: Brand New - Grade A cells Battery Type: Li-ion Voltage: 10.8 Volt (11.1 Volt compatible) Capacity: 5200mAh (Better than 4400mAh) 90 Day Money Back. Buy with confidence!