This is one of the best desk/computer lights I've bought. It has dual modes, warm (yellow ) light and cool (blue) light, with high or low settings for each, and comes equipped with a 110v AC adapter, or you can use the USB (as I do) for power. I needed a light to illuminate my keyboard during my late night YouTube excursions. Rather than turn on my bedroom light, I chose to go with a USB powered clamp style LED lamp. I don't want the whole room lit up (Although on Hi mode, this light pretty much does light up the whole room) The first one I tried was a disaster. It flickered sometimes, it would not stay put when I positioned it over my keyboard, and the light was just too dim to be of any use. So I trashed it and bought this one. This light meets all my needs, exceeds them actually, looks good, and stays in place where I clamped it. The only weakness I've seen in it is in the flexible "goose neck". Overall, the neck is very strong, and holds it's shape and position well. The problem is where the flex tube connects to the clamp. That's the only weak spot. It is very weak at that point, and will not hold position if the clamp is mounted to a vertical surface, in such a way as to direct the flex tube upward. (See Fig 1). If you mount it so that the light is aimed downwards, this would probably not be a problem. My solution was to attach a zip tie through the spring on the clip, around the flex tube to hold it at a vertical angle. (See Fig 2). It may not be all that pretty, but it works great. It stays put perfectly, and if I need to move it a little it is no problem at all. The clamp itself is exceptionally strong, and opens to over two inches. The switch is a dual rocker switch assembly, situated about eight inches down the cord from the clip. I used sticky-back Velcro tape to attach the switch to the edge of the backboard on my desk, right next to the light clamp. (See Fig 3). That way it stays put, and is easily accessible when I need it. All in all, it's the best late night keyboard light I've ever tried. Overall, I would definitely recommend it.