Doesn't make much of a difference in teeth color
I have purchased trays and bleaching agent from Amazon in the past.  That method is far superior to this charcoal powder, which I found to be virtually worthless.  It makes a mess in your sink and does not whiten very well.  God forbid you open the container with any force or you and your bathroom will be covered in black powder.  Ask me how I know that.
Rating: 1 stars