Little to No Tooth Sensitivity or Irritation Perfect for Touch-Ups or On-the-Go Whitening Elegant Satin Finish Fits in Pocket or Purse Great Stocking Stuffer or Gift Idea Made in the USA Shelf Life of Over 1 Year from Purchase No Need to Refrigerate Dentist Approved and Recommended Attractive Display Case Available (with 36 pen order) Customers LOVE It! The pen contains our own 36% carbamide peroxide gel that we make from the highest quality ingredients including kosher, vegan, GMO-free glycerin and natural flavoring.