USB Rechargeable Book Light for Reading in Bed, Portable Clip-on LED Reading Light, 4 Brightness Dimmable, Compact & Long Lasting [4 Brightness Adjustable] This small book light has 4 brightness levels available, you can choose the most suitable level for your eyes. You can set your favorite brightness as default with the book light for reading in bed. Plus, there are 5 LED beads scientifically installed so the light can be evenly distributed on reading pages. It is bright enough to illuminate the full pages, while it is dim enough not to disturb others nearby. No flickering, nor harsh light. [USB Rechargeable & Long Lasting] Standard USB rechargeable and compatible with any USB ports on your computer, adapter or USB outlet. This rechargeable book light has a built-in 500mAh battery providing you with 880 reading hours (depending on your brightness setting).