Amazon has been having a few sample boxes that if you have Amazon Prime, you get free shipping. Amazon sends you a credit for the full price, this one was $4.99. The credit can then be used towards the purchase of similar items. In this case, teeth whitening products.
This sample box contained a full size tube of Crest 3D White Toothpaste
A sample of Crest 3 D White whitening strips
Oral-B Glide Pro-Health floss
When they sent me the credit back I bought another tube of toothpaste because you can never have to many tubes of toothpaste in the closet and that stuff stays good forever or as long as it doesn't dry out.
If you haven't tried the sample boxes that Amazon has and you like some of the products that I keep showing you are in them, it's actually a pretty good deal since they give you the money back in the form of a credit to buy more stuff in the same category.