Efficient Product despite the price of the bottle as the few drops a day to use allow for a real economy. Just a disadvantage due perhaps to its concentration, a slight film appears on the surface and is very sticky on the spoon but not too bad on the most boring teeth to leave. Either it must be removed before drinking the water with which it was mixed (hoping that the active ingredients are not there), or you must swallow it directly into the throat without it hits the teeth ... even when you get there! Good stuff.
