rik_uk3 said:They are a small compact "coil Burner", uses Coleman type fuel. They burn hot but are not great at simmering. Lighting them is a technique you need to learn, and because of the small tank size, you don't get a great burn time.
That said, they are a well made bit of kit, would work well in a Swiss Kettle, under a steel mug, or a Swedish Army Trangia. If the price is right, they are a good stove