I asked the customer reps. and they said that is "authentic" and the one made by Clarisonic. After I received it, they refused to acknowledge that it was a fake, even though I compared it to my ACTUAL clarisonic brush head and found many differences proving that it's fake. I wouldn't be as mad if they just would say that it's not an actual Clarisonic brush head.
buying this from overstock saved me time and money. i couldn't get at store or doctor for this price, and it came so quickly right to my door. no tax or shipping! never knew they had items like this...i am becoming an overstock junkie!