Here is a new one available for Costco members.
Get a free sample of Crest Pro-Health Rinse. The free sample is 36ml. Head on over to the Costco page then click the “get a sample” button.
Fill out the form and enter in your Costco member ID to get your free sample. Some people try 12 random digits. Available for US residents only. Allow 4-6 weeks for delivery.