purchased from http://ob.factoryou***re.com/ and the head fell apart in my mouth as I was brushing. The bristle assembly and bristles went down my throat and caused choking. The Heimlich maneuver saved me. This website said there was nothing they could do. Reported to US Consumer Safety and Fed Trade Comission. I could have died! Oral-b had me do the scratch test and it was fake. Do not buy!