Replacement iRobot Roomba 551 - AeroVac Filter, Bristle Brush, Flexible Beater Brush and 3-Arm Side Brush - Kit Includes 3 AeroVac Filter, 1 Bristle Brush, 1 Flexible Beater Brush and 1 3-Arm Side Brush Replacement iRobot Roomba 551 - AeroVac Filter, Bristle Brush, Flexible Beater Brush and 3-Arm Side Brush The Brushes allows your Roomba to reach deeper into the carpet for a more thorough cleaning Replace filters every 2 to 3 months for best performance For Newer Version of the Roomba 551 - AeroVac. Please check your Roomba to make sure you are purchasing the correct parts On Sale for a Limited Time!