The 554189 Kirby Vacuum Primary Drive belt should be replaced every 6 to 12 months at the most keep your vacuum cleaner running efficiently. This belt is not for the brush roll. It is designed to fit the transmission component of your vacuum cleaner. The Kirby Generation Series geared drive belt is compatible with the following model cleaners: •G3 Model Cleaners •G4 Model Cleaners •G5 Model Cleaners •G6 Model Cleaners •Ultimate G Model Cleaners •Diamond Edition Model Cleaners •Sentria Model Cleaners