About this item Rechargeable LED Book Light: This lightweight (1.3 oz) clip-on light features a metal gooseneck for durability and adjustability, with 3 brightness levels and 3 color temperatures to suit your reading preferences. Long-Lasting Battery: The built-in rechargeable lithium-ion battery provides 4-80 hours of runtime depending on the brightness setting, and can be fully charged in 1.5 hours via the included micro USB cable. Secure and Versatile Clamp: The padded non-slip clamp opens up to 1.2 inches, securely gripping books, e-readers, tablets, and other thin objects without leaving marks.