DO NOT UNDER ANY CIRCUMSTANCE ORDER THIS PRODUCT
I had issues with the original brush heads breaking down in less than a month and thought it might be a design flaw.  I ordered this package of replacement heads and they did not look identical so I thought they might be improved.  I brushed my teeth for the second time with the new replacement brush head and OMG the head cracked, the bristles fell out and I had a mouth full of loose bristles in my mouth.  It wa gross!!!  I am returning the product and throwing  the AquaSonic in the trash.  Another fine product made in China.
Rating: 1 stars