Powerextra 2 Pack 7.2V 4000mAh Neato XV-11 XV-12 XV-14 XV-15 XV-21 Vacuum Cleaner Replacement Battery for Neato Robotics 945-0005 205-0001 945-0006 945-0024 2-Pack Neato replacement battery, Voltage:7.2V, Capacity:4000mAh, Battery Type:Ni-MH The 2pcs batteries should be used simultaneously. If one of them is used with an other brand battery improperly, this would cause errors based on different capacity and cells The batteries are CE certified, tested by manufacturer to match OEM products Replacement Battery for Neato XV-11, XV-12, XV-14, 945-004, XV-15, XV-21, XV-25, XV Signature 30 Days Money Back and 1 Year Limited Warranty