It does exactly what it says, I smoked pork ribs for 3 hours with very good results.
It is very convenient, especially for those who have a Napoleon grill. By removing a reflector, this box fits in its place. You only need to turn on this burner at the lowest intensity and in 5-10 minutes, smoking begins. The temperature should be around 95-100 degrees.
With the box full, it lasts about 1:00 to 1:15, then you have to refill it.
Normally, you should use Wood Chips, which are, however, very expensive (800g for 10€).
Personally, for smoking, I use pellets (9kg for 22€) since I have soaked them in water overnight, of course, pellets for grills and not pellets for heating stoves.