I bought this because of a favorable review by the Wirecutter from the New York Times.
The battery charges but the light itself does not come on.
I returned it.
Update: The vendor sent another. It also would not come on. However, there are no instructions provided. The vendor provided instructions in a message and those instructions worked! The on/off switch is located inside the bottom ring. The silver button is not for on/off but for the power selection. This is actually a grate item!