These little lens covers are great! I had been using pieces of Post-It notes to cover the lens on my desktop display and laptop cameras, but these little guys are perfect. At first I was afraid they might be too thick and my laptops might not close perfectly, but that has not been a problem on my Chromebook or my MacBook Air.Once installed, the sliding lens cover moves easily and stays in place, either covering the lens or leaving it open. I'm very happy with the products. The black version disappears on my desktop display, and the white one is almost unnoticeable on the aluminum frame of my MacBook Air.Two tips for installing them, however. Because they are very small, those of us with clumsy fingers should have a pair of tweezers on hand for the best placement. I did not use tweezers, but fortunately the glue on the back of the cover takes a few seconds to set, so I could nudge it into perfect alignment before letting the glue take hold. The other tip is to have the video camera *on* while you are installing the lens cover. This is so that you can see the little LED light that indicates the camera is active -- so you don't cover it up by accident.All in all, this is a great product, a great invention, and a great price.