Fancy Buying 14.4V 3500mAh Cordless Vacuum Cleaner Battery for iRobot 400 series, Roomba 4905 APS Battery Ni-MH battery, 3500mAh Capacity, 14.4V made with high quality battery cells 110 minutes run-time for your Roomba.High quality, high capacity battery for longer running time.convenient to use Easy install and it fits perfectly.Keep your Roomba cleaning up all the cat hair, cat litter and whatever else was on the floor Compatible with iRobot Roomba 400 Series Floor Vac models Advanced Power System (APS) Battery.(Note: This battery can only be charged by Ni-CD and Ni-Mh charger,not compatible with Lithium charger.) 12-MONTH EXTENDED WARRANTY - Safeguard features against incorrect voltage, short circuit, internal overheating.