Replacement iRobot Roomba 4233 Battery - For the iRobot Roomba 400 Series Robotic Vacuum Cleaners iRobot Roomba Battery Replacement for Roomba Discovery, Dirt Dog, Roomba 400, Roomba 4210, Roomba 4100, Roomba 4110, Roomba 4230, Roomba 4150, Roomba 415, Roomba 4000, Roomba 405, Roomba Create, Roomba 4130, Roomba 4220, Roomba 4225, Roomba 410, Roomba 416, Roomba 4905, Roomba 4160, Roomba 4200, Roomba 4400, Roomba 4300, Roomba 4310, Roomba 4260, Roomba 4420, Roomba 4418, Roomba 419, Roomba 423, Roomba 490, Roomba 4170 Battery Capacity: 3300mAh, Voltage: 14.4, Type: Nickel-Metal Hydride Premium Quality, One Year Warranty The Brush allows your Roomba to reach deeper into the carpet for a more thorough cleaning It's best to replace your brushes every 1 to 2 months