SCAM adverstising! Having located a particular research paper I noticed a "banner blog" about teeth whitening...the blogger wrote about obtaining free samples from 2 companies for under $10 shipping fee. Visited one company and could not sign on for the free sample; visited the second company and was able to order my sample for the shipping fee of $6.99. What the company does not clearly tell you is that this is not a free sample - even though that is how they pull you in. Once on their site, the switch happens; I actually signed up for a "free trial" of their product. After 15 days they charged my credit card for close to $79 for product I could not test, because it is impossible to push out of the syringe they provide. When I contacted them via phone, I was kept on the line for over 15 minutes by a very condescending person, who advised me that he "understands my problem", but it is my fault - I did not read through the terms and conditions. Lesson learned!