The height can be adjusted up to 20 inches (about 50.9 cm), providing you with a comfortable reading experience, reducing neck pressure, and saying goodbye to reading habits. It can be fixed on a desktop with a thickness of 2.2 inches, suitable for desktops, bedside tables and kitchen counters. When not in use, it can be folded at the edge of the table and does not take up desktop space. The base can rotate 360 degrees, which is very convenient for adjusting the reading angle. The hinge damping is . The base and arm are made of High-quality materials, providing a very stable grip on the desktop. The hinge can bear a weight of 2.5LB and the torque can be adjusted. The bookshelf can free your hands and is suitable for heavy books, recipes, sheet music and 13-inch (about 33.4 cm) tablets Colour:As Shown Material:B:P87 Aluminum-Plastic Panel Package Contents: 1 x Bookshelf Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.