I like this clamp light very much. It has more uses then lighting up your computer keyboard for example to furnish light when working on a TV tray table doing what ever project it may be. Just use a cell phone wall charger and USB cable to the clamp light. It has an on/off push button switch and three 3 light brightness levels. Also it doesn't get hot like a clamp light with an incandescent bulb would.
I took one star away because the clamp is a bit clunky.

Works fine. battery contacts are a bit fidgity. You might need to rotate the batteries around a bit to get it to be on but other than that its great and really super bright and easily lights up my entire desk from 5v USB!
It says 6v input but i'm guessing thats just a maximum.

it has 3 light modes when you push the switch. and it clicks. when you push it in
Super bright on the brightest setting. Dim but usuable at night on the lowest setting.
it works great as a nightlight

I wish It had came on the day it should of arrived instead of almost a week later.
it went to the wrong state and had to be changed to deliver from UPS instead of USPS
And then we missed it because we were asleep when they came at 9 AM
so it finally came and it came a few days later at around 7:20 PM!!

This is by far the brightest of the several keyboard lamps I've tried and the only one that really does its job. The only issue -- and it's not enough to make me return it -- is that the clamp won't stay attached to the edge of a desk youi want the gooseneck to point backwards (toward a keyboard tray). That means I have to clamp it to the KB tray itself, which means it shakes as I type. The root of the problem is that only the outermost half-inch of the clamp's arms has rubber on it to grip with, and that part doesn't always touch the desk when the neck is extended in the other direction. But I'll figure out a workaround. Definitely keeping it.

I picked this one for 2 reasons. It had 28 leds and it can stand on it's own.

Only 4 stars because the goose-neck is a bit flimsy and the spring isn't very strong.

I have a different led light I really love with 24 leds. It has warm and cool light and a high-low "beam" option. And the on-off switch is large and substantial. This light has a small button to push to change the lighting and you have to cycle through all of them before you get to the off position. And it's inconveniently located being under the cabinets. So, I also purchased a dimmer that works great. You can have all the leds on and adjust the ambient lighting. A great little gadget to go along with this.

I got this to light the corner under the cabinets. There is a piece of the cabinet frame that gives about 2 inches to attach it to. I have it there with the goose-neck out straight. I started out with it sitting, but it didn't light the corner very well. I just put it there to test it. I'd always thought it would be better up under the cabinets. My light is on the back of my monitor (it has a place with a ledge to grab to move it) and it's perfect stretched out. It gives me great lighting for my laptop so I can see the keyboard.

The spring on this is much looser than on my led light Wasn't sure it would stay. Mine's so strong it's all I can do to open it to attach it to anything. And it's goose-neck is much thicker with a plastic sleeve for extra strength, and it's longer. This light's neck is short (and I thought it was going droop, it just isn't strong), and it's bear, but it's long enough and it does a great job lighting our dark corner. And most importantly, Mom is very pleased. I told her if she didn't like it I'd trade with her, but she's happy and that's what I wanted!

This is a great lamp! I wanted a bright light for reading in bed, and as it turns out this is perfect. I have very bad vision, and this is excellent for my needs - would definitely be appropriate for someone with low vision needs. The lighted area is approximately 1.5" x 3", and has 3 light settings to vary the level of brightness. Bonus that it has a USB cable instead of having to use batteries all the time like many book lights. The clamp is large enough to fit over a headboard or on the edge of a table. Would definitely buy again.