The formula
What you’re brushing with.
The polishing pair
Calcium carbonate and dicalcium phosphate, the same family of mild abrasives a good toothpaste is built on. They take off what sits on the surface and leave what is under it alone.
No peroxide
Peroxide is what does the bleaching in most whitening kits, and it is why they come as a course with a break after — it can leave teeth and gums sensitive. There is none in here, so there is nothing to recover from between uses.
Xylitol and menthol
Xylitol does the sweetening — a sugar alcohol rather than sugar, which is why it turns up in oral care so often. Menthol is the cold bit. Between them, that is the taste.