It's a US-made pen called MAXXGEL. You get a pack of two for $15 and free shipping at Walmart. Each pen contains about 0.1-oz vs Intelliwhite's 0.12-oz.
I have used both the Intelliwhite Pro and Platinum pens and have had very good results with both. But after a while the cost of using the Intelliwhite can add up. The Maxxgel pens work just the same and saves me money. Highly recommend!