WITHit Disc Light, Silver, EASY TO SECURE: The WITHit Disc Reading Light is designed to fasten to books and e-book units easily and securely. FLEXIBLE NECK DESIGN: The light emitting from this book light fully illuminates the book pages and screen thanks to a flexible neck design. REDUCED GLARE: The design and shape of this reading light illuminate e-book devices like Kindles and the pages of books with reduced glare. This allows you to read in complete darkness and produces less strain on your eyes. EASY TO REPLACE BATTERY: The WITHit Disc book reading light comes with (2) CR2032 lithium coin cell batteries. Replacement batteries can be purchased on Amazon in bulk for approximately $0.25 per unit. PORTABLE and LIGHTWEIGHT: WITHit's portable reading light is easy to fold and can be conveniently stored in travel cases and backpacks. It is very lightweight at only 2.4 ounces, with dimensions of 8.5 x 1.5 x 4 inches.