When I was checking over my purchase, I was quite impressed with how well thought-out this visor is! I fit it to my head easily, then screwed the side knobs tight so the glasses would stay in place. The light has a switch for one, two, or three of the beams, and the glasses have I think five combinations of strength. I only need the one lightest one, but what an improvement! I'm going to use it for threading needles, crafts, reading crazy-small labels and print, and reading in bed at night while the other lights are out. My husband laughs at how I look like The Mad Scientist with it on, but he loves me and likes to laugh at me no matter what, haha!