TAUPO 9-Cell Laptop Battery for HP 620, Probook 4525S 4420s 4320 4320s 4320t 4321 4321s 4325s 4520 4520s 4425s 4326s 4320T 4421S, Compaq 320 321 325 326 420 421, fits PH06 PH09 593572-001 593573-001 Battery type: Li-ion; 9-cell; Capacity: 723wh, Voltage: 11.1V Compatible part numbers: 587706-121 587706-131 587706-221 587706-241 587706-251 587706-421 587706-541 587706-741 587706-751 587706-761 592909-221 592909-241 592909-421 592909-721 592909-741 593572-001 593573-001 Compatible Models: HP Compaq 320 321 325 326 420 421 620 621; HP 420 425 4320t 620 625; HP ProBook 4320s 4321s 4325s 4326s 4420s 4421s 4425s 4525s Grade A cells ensure fast charges and low power consumption; Built-in circuit protection ensures both safety and stability CE-/FCC-/RoHS-Certified for safety, 12 months hassle-free warranty