As mentioned by other reviewers, the gear at the base of the blender (which drives the blade) is made of plastic, and the teeth break off easily. I owned this product for 6 months, only making my daily smoothie and my son's protien shake, and three of the six gear teeth broke off. The major problem is this, however -- the blender is virtually impossible to return unless you live close to one of the "authorized" repair shops that Braun has listed on their website. You can't return it to Amazon after 30 days, and Braun will only repair or replace defective items through their difficult-to-find repair sites. Don't waste your money on this one.