Had many headband magnifiers different manufacturers in use.
THIS is meanwhile the best (and was also believed's not the cheapest).
Adequate Spot light through LED (for the finest things possibly necessary).
And most important: A very good quality of LUPE !!
Many others have / had a bad cut which is not exactly good for the eyes.
As an extra, there are cleaners, cleaning cloth attached.
One point deduction (actually half)
The headband has adjustment knob on back.
Since this hard plastic presses but unpleasant to the mind.
The problem was solved in my case a more than solid foam / leather loop of old headphones.