Amazon.com: HQRP AC Adapter Works with iRobot Roomba 531 533 536 537 551 561 563 564 571 577 578 600 611 790; 800/880 Series [Vacuum Cleaning Robot]; 80501 APS #80701 Power Cord Replacement : Electronics
Amazon.com: Synergy Digital Vacuum Cleaner Battery, Works with iRobot Roomba 531 Vacuum Cleaner, (Ni-MH, 14.4, 2800mAh) Ultra High Capacity Battery : Home & Kitchen