Instruct: Classify a review as either positive or negative.
Query: DESIGN DEFECT

My first 9650 lasted about 2 month. The Power switch button broke and leaked water. Then I bought the second one. It broke after 1 month , Same problem.If you compared 9650 with old model sonicare toothbrush, you can find that the power button on the old model is much bigger than 9650's.